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Am I a human? Yes. Can I type phi off the top of my head? No. enter image description here

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That's Phi, not Theta. – Michael Kristofik May 5 '10 at 13:05
This is probably a bug. Urrgh what the what? – the_drow May 5 '10 at 13:06
@Kristo and all - thanks. Maybe that's why... 8-\ – Sky Sanders May 5 '10 at 13:08
Note that if you would have typed whatever you wanted instead, it probably would have worked as long as the first was "corrected". – Gnoupi May 5 '10 at 13:09
How do we know that you're human unless you pass the CAPTCHA? Everyone be on your guard!! "Code Poet" is a human impersonator! He's trying to enlist your help to beat the CAPTCHA! – devinb May 5 '10 at 13:15
to add to Gnoupi's answer, SO uses re-captcha one of the words is known and one of the words is a scan from an old book. By giving the captcha to many people, they can accurately determine the scanned words the computer can't recognize. Effectively using small amounts of peoples time as powerful computer power to electronify books. – Lumpy May 5 '10 at 13:18
@Lumpy - if your comment had a checkmark next to it, it would be marked check. – Sky Sanders May 5 '10 at 13:44
As designed. A robot would not head off to meta, post this question, learn how to enter the CAPTCHA, then return to the page and complete the challenge. So clearly you are not a robot, and the CAPTCHA worked! – Craig Stuntz May 5 '10 at 15:07
@Craig I don't know. That sounds exactly like a try - catch to me. try { ReadCaptcha(); } Catch(InvalidCharacterException ex) { PostToMeta();RetrieveAnswerFromFoolishHumans();} Finally { SpamDeluge(); } – devinb May 5 '10 at 15:22
Are we human? Or are we dancers? – Daniel Daranas May 5 '10 at 20:20
I got this recently with a photon-symbol, and also one with chinese letters >< – rightfold May 5 '10 at 21:50
Related: TODAYS REVISIONS WTF?! – rightfold May 5 '10 at 21:56
@Koning - i noticed that too. interesting.. – Sky Sanders May 5 '10 at 22:30
As for revisions, I had my turn at it :) – uɐɯsO uɐɥʇɐN May 6 '10 at 0:08
@Earlz: So...? They're just as bad as your titles. – uɐɯsO uɐɥʇɐN May 6 '10 at 0:17

16 Answers 16

up vote 46 down vote accepted

According to reCAPTCHA:

Each new word that cannot be read correctly by OCR is given to a user in conjunction with another word for which the answer is already known. The user is then asked to read both words. If they solve the one for which the answer is known, the system assumes their answer is correct for the new one.

So therefore if nobody else figured out this one, you would be the first and you could legitimately type anything and succeed at it.

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So that would explain why it let me through when I accidentally mistyped a captcha... – Zach Johnson May 5 '10 at 21:17
Yeah, the policy is harass some internet users to get your work done for free... – ufotds May 19 '14 at 19:21

Pfft... that's easy. Try this one:

worst captcha ever

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I smell a robot! – devinb May 5 '10 at 14:10
Burnt waffle reform. easy. – Sky Sanders May 5 '10 at 14:40
@Jon: I don't think that █ is an 'ARABIC PLACE OF SAJDAH' (U+06E9) – kennytm May 5 '10 at 14:53
@Kenny: Ummm... they had an unfortunate fire? – Jon Seigel May 5 '10 at 14:57
Pretty easy on on iPhone >++++++++++[>+++++++++++>+++++++++++>++++++++++++><<<<-]>>+>----><<<<>.>.>. – rightfold May 5 '10 at 21:59
Is it ▓ Reform? – Aarobot May 5 '10 at 22:00
It looks kind of like a cake. Maybe it's "torte" reform. – user164291 Aug 8 '12 at 20:53

As promised, here's the one I got a few days ago:

alt text

Edit: One more from just now (looks like they are scanning math books):

alt text

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++ wtf indeed. . – Sky Sanders May 5 '10 at 22:50

This is a trick question: you fail if you can type it.
The cat and mouse game continues...

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Remember that, if the challenge is too "hard" to solve, you can request a new one with the "refresh" button.

Recaptcha and the "new challenge" button enclosed in a yellow freehand circle.

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Klaatu ampliti ni*hack cough*! – user164291 Aug 8 '12 at 20:54

Readable, just confusing. It seems like reCAPTCHA is now digitising house numbers on Street View as well ;)

enter link description here

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Nice. And odd that they know where to find the number, but then still need a human to confirm its value ;-) – Arjan Mar 28 '12 at 5:47
I've seen this recently. No else that I know agreed with me, about those being house numbers though. I am so happy that there is some else who believes that they are house numbers too! – Ellie Kesselman Aug 8 '12 at 20:24
Seriously dafuq!! o.O – Bhuvan Rikka 웃 Aug 16 '12 at 9:34
Are there 2 pi before number? – Danubian Sailor Aug 23 '13 at 9:07

You misunderstood - you are supposed to solve the equation as well.
I know it's tough but we have to keep the cyborgs out of Meta.

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alt text

Now, isn't at least one of these supposed to be a real word?

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Google: 'Your search - joutandt - did not match any documents'. lolz - what are the odds of 0 google hits on a single word consisting of ascii characters? – Sky Sanders Aug 18 '10 at 19:39
What's more impressive, we're discussing it on the Internet and it's still a Googlenope! (Also, I totally thought the second "word" was in Arabic at first.) – Pops Sep 17 '10 at 18:27
Clearly it's "joutandt OOMMG!!!" – Ben Lee Mar 28 '12 at 6:22
No, "18 15 23 44" don't count as a word in my book, even if rotated by 90°. – MvG Oct 5 '12 at 19:56
@SkySanders Your comment is the top result, but nowadays there's also a Google Books results from something published in 1813... – Izkata Aug 3 '14 at 22:06


(or use LaTeX \phi_{M,P}(x).)

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&phi; doesn't work though :) it's clearly the capital letter Phi: ɸ. I am not sure of the HTML code for that though. – Joshua May 5 '10 at 13:49
@Joshua: The capital Greek Phi (&Phi;) is Φ (U+03A6), not ɸ which is the Cyrillic Ef (U+0444). There's also a phi symbol ϕ (U+03D5) which may render like the image, depending on the font. – kennytm May 5 '10 at 13:54
@Joshua: &phi; and &Phi; -> φ and Φ – perbert May 5 '10 at 14:23
You know, providing LaTeX equations in captchas would be excellent for to keep out the riff-raff. They're always complaining that they get too many elementary-level questions there... ;) – Ether May 5 '10 at 14:49

I actually got 4 Greeks in a row. Sharing my favorite for posterity:

adessurn ... aw crap.

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First of all, I am human but no human being can decipher the ReCAPTCHA I just encountered. enter image description here

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Someone skipped differential calculus. – Bavarious Apr 23 '11 at 8:45
You only need to type "helects" for that – YOU Apr 23 '11 at 8:49
@YOU: Oh, there's no need for capitalization? – Hendrik Vogt Apr 23 '11 at 9:17
@Hendrik, Yeah, I used to type like that, and It works, IIRC. – YOU Apr 23 '11 at 9:25
What's so hard about (\deltaa_i)/(\deltaa_(i-1))? – Tom Wijsman Feb 25 '12 at 16:51
@TomWijsman: It's \partial a_i/\partial a_{i-1} also pronounced "del", "dou", and other weird stuff.… – Manishearth Mar 28 '12 at 6:24
I guess so, that's over the top of my head... – Tom Wijsman Mar 28 '12 at 6:30

This is the best (or worst) CAPTCHA I've recieved.

enter image description here

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Oh, that's \sum_(i=0)^n((-1)^n)/(2n-1^(\Delta^n))). – Tom Wijsman Feb 25 '12 at 16:50
@TomWijsman: it's clearly (-1)^50 :) – CSᵠ Feb 27 '13 at 21:20

I just got one with an integral from -∞ to ∞. Is reCAPTCHA digitizing math books this week?

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It's been for some time. I recall an integral from a few weeks ago. – perbert May 5 '10 at 17:16
Hmmm... I wonder if we're supposed to solve these? – Bill the Lizard May 5 '10 at 20:34
@Bill: But there wasn't anything to integrate -- just the integral symbol. That's why it was so frustrating! – mmyers May 5 '10 at 21:40

I would have entered ompx.

You can also just press F5 to get another one.

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-1 anti-ReCAPTCHA – Pops May 5 '10 at 14:20
Is that popular demand? Don't think so. – BalusC May 5 '10 at 14:24

I think it is the symbol of diameter. Well... I can: ∅ and ϕ

This are some details of phi:

UTF-8: 0xCF 0x95
UTF-16: 0x03D5

C-form (octal escaped UTF-8): \317\225
XML-form (decimal): &#981;

Symbols in linx

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Are you a human? – Sky Sanders May 5 '10 at 13:08
@code poet: Yes. In linux there is a very handy app that allows you to access all symbols. – Martijn Courteaux May 5 '10 at 13:10
NULL SET and PHI are not the same glyph. – quack quixote May 5 '10 at 13:25
@Quack Quixote: correct, the correct glyph is U+03D5 Greek Phi Symbol (referring to the posted image, it is the incorrect glyph). Windows also has a character lookup, called the Character Map. – Joshua May 5 '10 at 13:38
Sadly, X's Alt Gr key mapping includes ø, but not phi. – perbert May 5 '10 at 14:21
@Mart: What app is that? – John Mar 5 '11 at 2:17

Distorted text CAPTCHAs can be a little stressful also!


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When did SE turn into reddit ? – Pogrindis Jun 2 '15 at 16:00

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