What is Captcha❓ Types and Examples – Wallarm
It is a CAPTCHA that decides whether a client who is trying to gain access to a service or data is really a bot. While these tests can assist with halting vindictive bot action, they are a long way from is CAPTCHA? A CAPTCHA test is used to identify whether an internet user is a human or a bot. CAPTCHA is a short form for “Completely Automated Public Turing Test to Distinguish Robots from People. ” On the Internet, CAPTCHA and reCAPTCHA tests are frequently encountered. Such experiments are one way to monitor bot migration, however the approach has certain drawbacks. Despite the fact that CAPTCHAs are intended to impede mechanized bots, CAPTCHAs are themselves robotized. They’re customized to spring up in specific puts on a site, and they consequently pass or bomb clientsHow does CAPTCHA work? Customers should separate letters in exemplary CAPTCHAs, which are as yet being used on certain online areas today. The letters are misshaped with the target that bots are not committed to have the choice to recollect them. To coast through the evaluation, clients need to interpret the twisted substance, type the right letters into a plan field, and present the development. On the off chance that the letters don’t work with, clients are actuated to attempt once more. Such tests are standard in login structures, account information exchange structures, online audits, and web business checkout pages. The thought is that a PC program, for example, a bot will be not prepared to decipher the twisted letters, while an individual, who knows about seeing and interpreting letters in a wide extent of settings – distinctive printed styles, diverse penmanship styles, and so forth – can all around remember them. The best that different bots will truly have to do is input some irregular letters, making it really dubious that they will finish the assessment. In this way, bots bomb the test and are hindered from partner with the site or application, while people can keep on utilizing it like common. Progressed bots can utilize AI to see these harmed letters, so such CAPTCHA tests are being supplanted with more inconsistent tests. Google reCAPTCHA has urged distinctive different tests to figure out human clients from bots. Since the introduction of CAPTCHA, AI-based bots have been developed. Customary CAPTCHAs with tests composed in course of action accreditation are more interesting to these bots. Considering this new turn of events, fresher CAPTCHA methods depend on extra shocking tests. For portrayal, reCAPTCHA demands you to tap on a particular spot and deferral until the look at is finished. What are CAPTCHAs used for? At the point when online applications request client input, CAPTCHAs are usually utilized. Accept that you’re maintaining an online business and you need to give your clients the choice of leaving item surveys in a remarks area. For now, you should guarantee that the entries are genuinely from your customers or, possibly, from human site guests. You’ll spend a generous segment of your time going over frequently delivered spam comments – and in the most dire outcome imaginable, you’ll team up with your enemy. You may decrease the danger of this occurrence by consolidating a CAPTCHA into your site, which expects clients to demonstrate that they are human prior to presenting a remark. Manual human tests may now be found in pretty much every region where human customers ought to be recognized from bots. In contrast with online charts or web affiliations, for example, web crawler affiliations, this fortifies choice systems for email affiliations, warning, affiliations, and social affiliations. Examples of type CAPTCHAText-based, picture-based, and sound-based CAPTCHAs are the three types of CAPTCHAs available CAPTCHAsThe most standard kind of check is text CAPTCHAs. These CAPTCHAs can fuse prominent articulations or explanations, similarly as uncommon digits and letters blends. Some substance-based CAPTCHAs break down different kinds of capitalization. These characters are shown in an odd style by the CAPTCHA, requiring translation. Characters that are scaling, incensed, or turned would all have the option to be coordinated with malevolence. It may moreover join suitable segments like tone, foundation wobbliness, lines, winds, or spots just as covering characters. Despite the way that it may be difficult to understand for individuals, this opening plans for bots doing lacking substance affirmation computations. Strategies for making text-based CAPTCHAs include: GimpyThe gimpy selects a handful of emotionally charged words from a rundown of 850 words and conveys them in an unusual manner. EZ-GimpyIt’s an assortment of Gimpy that just utilizes a single word. Gimpy-rThis picks reassuring letters, then bends and embellishes them with foundation discontent. Simard’s HIPThis method picks alphabets and numerals at random and then alters them with curves and CAPTCHAManual human tests utilizing pictures are developed on in a split second clear graphical components instead of a vexing strategy including digits and letters. At last, a few photographs of ordinary things are compared. The customer should feature which photographs have all the earmarks of being the most significant or show which ones tackle a semantic issue. Google, then again, utilizes Google Street View CAPTCHAs that expect clients to enter a street address or a road sign into the material box. Most clients can address an image based CAPTCHA very quickly. Regardless, a PC program’s capacity to acquire an addressed picture, then, at that point request it’s anything but, and afterward work out near one is restricted partly. Thusly, picture-based CAPTCHAs give preferred security over text-based CAPTCHAManual human tests are a sort of development that permits individuals to get to obstructed sites. These CAPTCHAs are as often as possible utilized related to message based and picture based CAPTCHAs. Customers ought to expect a progression of moving characters or numbers in a decent CAPTCHA. Bots can’t separate crucial characters from establishment shock in these CAPTCHAs. Concerning bots, these mechanical gatherings, like substance-based CAPTCHAs, can be difficult for individuals to or verbal problemsA CAPTCHA framework that also satisfies the needs of the purportedly weakened utilizations science concerns or problems is used to bypass spambots. When necessary, a screen reader may be used to examine an assignment like the one below, implying that it can also be used by clients with non-visual yield contraptions. These mathematical aspects aren’t too complex to interpret, but the problem is that they don’t solve a really progressive balance for PCs, which are designed to coordinate numbers. This form of CAPTCHA is frequently coupled with various types of text scorn, making it nearly impossible to interpret for screen viewers. On the off chance that the outcome is a word as opposed to a number, or if a solitary digit of the outcome should be contribution because of some lucky new turn of events (for instance, discover 7 x 7 and just enter the principal digit of the outcome in the compartment), it is intrinsically harder for applications. The CAPTCHA game methodology would be 4) if the outcome was 49. CAPTCHAs are also used in the same way as enrollment tries are. They incorporate exercises errands and general information requests. Frequently, and with a clear connection to the specific site. Before moving on to the next level of a conversation regarding SMF (Simple Machines Forum) programming, the visitor must respond to two tasks regarding the topic. What is reCAPTCHA? As an option to conventional CAPTCHAs, reCAPTCHA is a free instrument that assists with Google offers. Shortly after its inception, Google purchased reCAPTCHA from some scientists at Carnegie Mellon University in 2009. reCAPTCHA is a more advanced version of the standard CAPTCHA tests. Some reCAPTCHAs, like CAPTCHA, require consumers to submit images of text that PCs have difficulty interpreting. Unlike traditional CAPTCHAs, reCAPTCHA gets its content from real images: photographs of street addresses, text from printed books, text from historical newspapers, and so some time, Google has improved the usability of reCAPTCHA tests so that they no longer need to rely on the previous approach for seeing hazy or destroyed content. Various reCAPTCHA tests are used to combine information:Picture acknowledgmentCheckboxGeneral client conduct evaluation (no client association by any means)What are the disadvantages of using a CAPTCHA? Awful customer experienceA CAPTCHA test can encroach upon the movement of what customers are endeavoring to do, giving them a negative point of view on their experience on the web property, and provoking them giving up the webpage page all around usable for obviously blocked individualsThe issue with CAPTCHAs is that they rely upon visual insight. This makes them practically incomprehensible, for people who are really outwardly debilitated, yet for anyone with truly hindered vision. These tests can be deceived by botsAs portrayed above, CAPTCHAs are not totally bot-proof and shouldn’t be relied on for bot the chiefs. Can CAPTCHAs stop bots? The quantity of connection required for the site is considerably decreased when a CAPTCHA is employed to keep automated spams out while enabling people to pass. Administrators of sites with original material won’t have to check submissions on a frequent basis. Diverse CAPTCHA suppliers are attempting to compensate for AI degrees of progress by making the tests verifiably more severely orchestrated. Manual human tests finally become unsolvable, paying little notice to how long it requires. Turing test and CAPTCHAA Turing test assesses a PC’s capacity to imitate human discourse. In 1950, Alan Turing, a pioneer in the control, proposed the Turing test. The Turing test is “passed” if a PC program’s exhibition is unclear from that of a human all through the test – on the off chance that it’s anything but a human would. A Turing test isn’t tied in with tracking down the right courses of action; it’s about how “human” the suitable reactions appear, whether or not they’re right or mistaken. A CAPTCHA isn’t a Turing test, despite the fact that it isn’t a “Open Turing test” – it isn’t at the stage where anybody can tell if a human client is actually a computer program (a bot) or not, rather than attempting to determine whether a computer is human. To do this, a CAPTCHA must present a simple job that people can perform while PCs struggle. Seeing text and images follows these rules for the most part.
8 widely used captcha examples – Lets Nurture
Completely Automated Public Turing test to tell Computers and Humans Apart. (Blinks several times. )
Famously known CAPTCHA is a type of challenge test used in computing to identify whether the user is human or not. CAPTCHA comes in several sizes and of different types. These all works quite well against spam some are harder to solve, some are fun and some will benefit you monetarily on your website. There are many CAPTCHA examples but the most widely used are mentioned below:
Drag and Drop
Tic Tac Toe
1. The standard word captcha with an audio option
This is the standard captcha available whenever a security check-in is required, where you need to write the word which has been displayed. But some of the distorted word images are hard to solve. To get this pass through it allows you to use the option of “Recaptcha”, in order to receive a new one. There is also an audio option if you are unable to visually make out the word. These are the most commonly used while preparing a form in website development or app development.
2. Picture identification of captcha
This captcha provides users for selecting the elementary choice of selecting the correct image that they are asked to identify. This type of captcha usually never gets harder than the basic images, so you do not have to worry about your users not being able to depict them.
3. Math Solution
This type of captcha involves basic math problems and if your user cannot solve this basic questions then probably you do not want them to visit your website further. This provides with easy to read numbers and must be solved to get through the captcha.
4. 3D captcha
These type of captchas are called as “Super Captcha” because there are several 3D images which include both images and words and thus becomes hard for one to solve it.
5. Ad-injected captcha
These type of captcha helps your websites to earn some extra cash by publishing it, which in turn also helps in terms of brand recognition.
6. jQuery slider Captcha
This is a plugin which gives you the ability to add captcha to your forms which are easy to use. This plugin is very useful to keep the spammers away. This plugin lock is disabled until a person slides it to enable it.
7. Drag and drop Captcha
This is also one of the easy to use captchas. It is jQuery based which allows user to drag the required object or shape to pass through the security gate.
8. Tic Tac Toe Captcha
This captcha which involves gamification was designed for fun and an easy way to ensure that only humans can interact with your website. The captcha that does not hurt that much.
LetsNurture is a leading IT service providers with a vast range of solutions to offer. We have in-house expertise in website development, Android app development and iOS app development. We have diversified solutions range to fulfill your IoT development, BLE based solutions and Chatbot development requirements. If you are a business looking for similar solutions, our capable in-house team will be happy to cater your requirements. Please feel free to contact us at
reCAPTCHA v2 vs v3: efficient bot protection? [2021 Update]
The promise of Google’s reCaptcha v3 is to prevent bot traffic to your website, without the user friction we all associate with google reCaptcha v2. But does reCaptcha v3 keep its promise?
Let’s take an honest look at what reCaptcha v3 can and cannot do for your website security. We’ll recap the differences between reCaptcha v2 vs v3, uncover the pitfalls of reCaptcha v3 configuration, and sum up what a truly effective bot protection and mitigation solution must deliver.
Here’s what we’ll cover:
ReCaptcha v2: Hard on humans, too easy on bots
AI to solve reCaptcha v2 challenges
ReCaptcha v3: Easy on humans, except website admins
Mapping reCaptcha v3 user scores to actions
There’s no feedback loop
Why reCaptcha is not a bot management solution
The reCaptcha alternative which really stops bots
Without further ado, let’s dive in.
What is reCAPTCHA?
First, a quick recap: reCaptcha is a security service provided by Google, currently used by more than 6 million websites. Its purpose is to protect websites from bot-driven abuse.
Google promotes reCaptcha as a free service, but in reality it’s only free for accounts that generate less than 1 million API calls per month.
For heavier reCaptcha uses, Google recently started charging a fee. Accounts that generate more than 1, 000 calls per second or 1 million calls per month must sign up for a reCaptcha Enterprise account. For up to 10 million calls per month, the fee is 1$ per 1, 000 calls (beyond 10 million calls, custom fees apply). So for example, if your website generates 3 million calls per month, your reCaptcha bill will be $3, 000.
Most websites are still using reCaptcha v2, which was launched in 2014. If a website visitor’s behavior triggers suspicion, reCaptcha v2 will serve a challenge that the visitor must solve to prove they’re human.
As users, we’re all familiar with the various versions of reCaptcha v2. Sometimes, all you need to do is check a box that says “I’m not a robot”. Other times, the reCaptcha will challenge you with an image or audio recognition task. Whether or not you get the full challenge will depend on how confident Google is that you really are a human.
Aren’t we all computers in a simulation anyway?
reCaptcha v2 is based on an “advanced risk analysis system” which relies quite heavily on Google cookies. If someone is browsing the web using Chrome, or has been logged into a Google account for a while, they’ll most likely just have to tick a box. A Firefox user who has disabled third-party cookies, on the other hand, is much more likely to get a difficult image recognition challenge.
But not everyone uses Chrome, and not everyone is comfortable using Google’s services. In fact, people are increasingly concerned about their online privacy. They prefer privacy-conscious browsers such as Firefox or Brave, and might even use a VPN to browse the Internet. ReCaptcha v2 will give these users tougher challenges, which will degrade their user experience and lead to lower conversion rates.
Furthermore, due to the ubiquity of reCaptcha v2, cybercriminals have found increasingly efficient automated solutions to bypass even the most difficult reCaptcha v2 challenges.
Some bots leverage recent progress in artificial intelligence to solve reCaptcha v2 challenges. More specifically, advanced neural networks help train AI models in such a way that they can automatically solve captchas.
It’s quite ironic, in a way: Google uses reCaptchas to train their image and audio recognition AI models, and cybercriminals use those advances in AI to beat the reCaptchas. The circle of digital life!
Cybercriminals can also outsource reCaptcha solving to human workers in low-cost countries via so-called Captcha farms.
If you want to learn more about Captcha farms and Captcha farm detection, watch this webinar recording:
Webinar: Are Captcha Farms outsmarting your website?
Having listened to some of the complaints from its users, Google developed reCaptcha v3 to provide a better user experience. Unlike v2, reCaptcha v3 is transparent for website visitors. There are no challenges to solve. Instead, reCaptcha v3 continuously monitors the visitor’s behavior to determine whether it’s a human or a bot.
For each request the user makes, reCaptcha v3 returns a score between 0 and 1 that represents how likely it is that the request originated from a bot. Close to 0: sorry, you’re a bot. Close to 1: congrats, you’re a human.
In order to improve the accuracy of this score, website administrators can define specific actions, such as “sending a friend request” or “homepage” to help the reCaptcha understand how normal user behavior will vary depending on the context.
However, there’s a catch. While reCaptcha v3 clearly improves the experience for human users by eliminating the need to disrupt their browsing with reCaptcha challenges, it also raises new problems for website administrators.
With reCaptcha v2, the only required action was to verify whether the user correctly solved the challenge or not. With reCaptcha v3, you now need to decide which action to take depending on the score. Getting this configuration right is a tricky task for even the most experienced webmaster.
For each action a user makes on your website, you have three possible responses:
Give the user access to the requested resource
Ask the user to solve a v2 reCaptcha to determine if they’re human
Block the user (hard block).
This means that you need to decide, for each action, where you want to place the threshold for a particular response. Will you block the user when their score falls below 0. 25, or will you serve them a v2 reCaptcha? What about 0. 15? Will you fully block them then, or does 0. 10 seem more appropriate? There are no clear-cut answers, which is what makes these questions so difficult.
The issue here is that the stricter you make your thresholds, the more likely you are to block actual users. The contrary is also true: the looser your thresholds, the more likely you are to leave bots undetected. You’ll need to make an unpleasant compromise between not blocking too many users and not allowing too many bots.
The reCaptcha v3 dashboard will show you a distribution of user scores for each action on your website. But that’s not enough to help you understand whether you’ve set the right thresholds, because there’s no other information to help you better understand those users.
This is particularly true when you consider that the Internet is far more diverse than we often imagine it to be. Sure, the majority of your legitimate users might browse the Internet with Chrome, Edge, or Safari, but what about the 10% of people who don’t? What about your privacy-savvy users? Their user scores will be significantly lower, and do you really want to make their lives harder with v2 reCaptchas or by blocking them without a second chance at all?
Setting blocking and authorization thresholds without a proper monitoring mechanism is like playing Russian roulette with your website’s traffic. However, collecting, storing and analyzing enough data to set these thresholds accurately requires deep bot detection knowledge and would entail significant software development costs.
There’s another problem with reCaptcha v3. It uses behavioral detection to predict whether a given request originates from a human or not. While behavioral detection is indeed extremely helpful for detecting advanced bots, learning how to accurately distinguish bots from humans requires very large data volumes.
Before reCaptcha v3 can make a decision based on behavior, It also needs a user to interact with your website for a while before it can make an accurate decision. When used alone, it therefore leaves your site vulnerable to large-scale distributed crawlers that leverage IP rotation to frequently change their IP address.
Here at DataDome, we did a quick experiment to determine whether reCaptcha v3 also uses basic client-side fingerprinting signals. Turns out it does. While v3 can easily detect “naive” bots, such as those that don’t remove the navigator. webdriver attribute or use unpatched Selenium bots, bots that forge their fingerprint will easily bypass detection.
We created a Headless Chrome bot and used the Puppeteer extra framework to forge its fingerprint. The screenshot below was taken by that bot. It had obtained an almost-perfect user score of 0. 9. A perfect intruder.
While reCaptcha v2 and v3 can help limit bot traffic, both versions come with several problems:
User experience: human users hate the image/audio recognition challenges
Captcha farms and advances in AI allow cybercriminals to bypass reCaptchas
Defining the right thresholds for v3 user scores is a very difficult task
There’s no way to monitor false positives and negatives
Advanced bots are able to bypass them.
The bottom line is that neither v2 nor v3 serves as a replacement for a proper bot management solution.
The DataDome SaaS bot protection solution offers a reCaptcha alternative which actually works for e-commerce and classified ads websites. Here’s how we address each of the above-mentioned problems.
Like reCaptcha v3, DataDome is transparent for human users. There’s no challenge to solve. But unlike v3, DataDome uses a wide range of techniques to distinguish bots from people: behavioral analysis, device fingerprinting, IP reputation, and more. All these approaches are invisible to human users.
In fact, DataDome’s customers frequently report that the user experience has improved. For some customers, bots could represent 40% of their traffic. This took a heavy toll on their server loads and, as a result, on the performance of their websites. Activating DataDome instead of reCaptcha significantly improved loading speed and user experience, since bots didn’t swamp their servers anymore.
Captcha farm and AI detection
DataDome does use Captchas as a feedback loop to enable blocked human users to continue their navigation. However, we don’t consider a solved Captcha as undisputable proof. We’ve developed different approaches to make sure that Captchas are solved by actual people, not by Captcha farms or neural networks. Every day, we invalidate thousands of forged Captcha responses.
Blocking and allowing thresholds
If you are looking for a reCaptcha alternative that works on autopilot, DataDome has you covered. Once you’ve installed our server-side module and our mobile SDK, and whitelisted your partners’ bots, you don’t need to add any other detection logic or thresholds. Our advanced detection engine takes care of figuring out whether your visitors are human or not, so there’s no complex exercise for you to go through.
Unlike reCaptcha v3, DataDome also recognizes good bots such as less popular search engine bots, content aggregators and SEO bots. This means you don’t have to worry about forgetting something or making a mistake and accidentally degrading your SEO rankings.
Of course, if you want, DataDome gives you the possibility to add custom detection logic or whitelist some of your traffic based on criteria such as IP, country, user agent, and so on.
Thanks to our advanced detection engine, DataDome (unlike reCaptcha v3) has an extremely low false positive rate: below 0. 01%. I. e., per 10, 000 Captchas served, less than one is seen by a human. In those rare instances where that happens, our real-time feedback loop propagates the information to our detection engine in less than 2 ms to ensure we don’t hard block humans.
To deal with false negatives (letting bots through), DataDome’s detection engine constantly learns new bot patterns using AI. It also leverages bad traffic detected on one website to protect other websites. But we also keep humans in the loop: our team of data analysts conducts frequent traffic reviews to ensure we don’t miss any bots.
DataDome also comes with an intuitive dashboard which enables you to monitor your main traffic metrics, such as the volume and nature of bad bot requests, the number of Captchas served, etc. If you want to explore your traffic in more detail, you can do so with a real query language that you can use to explore a wide range of dimensions, such as IP address, country, type of bots blocked, and more.
Detecting advanced bots
Every day, DataDome encounters new advanced bots. Our detection engine uses behavioral AI detection, advanced fingerprinting, and IP reputation to make sure we detect even the most cunning bots. Contrary to other bot management solutions that analyze requests in batches, DataDome analyzes each request in less than 2 ms to determine if it originated from a bot or a person.
The bot we discussed above, which received a 0. 9 user score with reCaptcha v3, would be caught immediately with DataDome. Our fingerprinting module can detect advanced bots that use residential IP proxies, forge their fingerprint, or use real browsers and headless browsers automated with modified Puppeteer. The same goes for advanced Playwright bots or modified Selenium bots, even if they modify the Chromedriver binary. In a single request, we stop them.
While reCaptcha v2 and v3 can help block some bot traffic, they come with many problems. They degrade the user experience, can be bypassed with Captcha farms or AI, have no real feedback mechanisms, can lead to false positives and negatives, and don’t detect advanced bots.
Neither version of reCaptcha should therefore be considered as a proper bot management solution.
Want to see what type of bot traffic is on your site? You can test your site today. (It’s easy & free. )
Frequently Asked Questions about different types captcha
What is the most commonly used CAPTCHA?
There are many CAPTCHA examples but the most widely used are mentioned below:Word solving.Audio.Branded.3D.Math solution.Drag and Drop.JQuery Slider.Tic Tac Toe.May 22, 2017
Which is better reCAPTCHA v2 or v3?
While reCaptcha v3 clearly improves the experience for human users by eliminating the need to disrupt their browsing with reCaptcha challenges, it also raises new problems for website administrators. With reCaptcha v2, the only required action was to verify whether the user correctly solved the challenge or not.
What is the difference between CAPTCHA and reCAPTCHA?
CAPTCHA is the human validation test (usually the blurry squiglly letters that need to be deciphered) used by many sites to prevent spam. reCAPTCHA is a reversed CAPTCHA – the same test, used not only to prevent spam but to help in the book digitazion project.Jun 30, 2015