SEARCH

How-To Geek

When CAPTCHAs turn Mathematically Evil [Image]

Typing these CAPTCHAs in should be as easy as can be, right?

Top CAPTCHA Image

Hardest Captcha of all time?…Really? [via Reddit]

Bottom CAPTCHA Image

Really, Captcha? [via Reddit]

Akemi Iwaya (Asian Angel) is our very own Firefox Fangirl who enjoys working with multiple browsers and loves 'old school' role-playing games. Visit her on Twitter and .

  • Published 10/14/11

Comments (17)

  1. MJ

    I got those from time to time. Actually, I think that reCaptcha only tries to see if several people wirtes that “word” the same way. If they do, it will be added to the dictionary. The other word in these cases is already in that dictionary and will be the word checked to clear your way.

  2. Ollie

    The easy way to deal with those is just to leave out the formula. A reCaptcha always consists of one “word” taken from a scanned document (in these examples the formulae) and one “word” generated by reCaptcha (usually just a random sequence of letters). reCaptcha only knows for sure what the generated “word” is, so that’s the only one you actually have to get right, and in fact you can leave the other one out entirely.

  3. captchmeout

    i got the chinese captcha

  4. Anonymous

    Easy as “PIE”!

    (3.14159265…)

  5. Pie to the hundred thousanth digit, (I think)

    Reply – Easy as “PIE”!
    No its not :D
    3.
    1415926535897932384626433832795028841971693993751058209 7494459230781640628620899862803482534211706798214808651 3282306647093844609550582231725359408128481117450284102 7019385211055596446229489549303819644288109756659334461 2847564823378678316527120190914564856692346034861045432 6648213393607260249141273724587006606315588174881520920 9628292540917153643678925903600113305305488204665213841 4695194151160943305727036575959195309218611738193261179 3105118548074462379962749567351885752724891227938183011 9491298336733624406566430860213949463952247371907021798 6094370277053921717629317675238467481846766940513200056 8127145263560827785771342757789609173637178721468440901 2249534301465495853710507922796892589235420199561121290 2196086403441815981362977477130996051870721134999999837 2978049951059731732816096318595024459455346908302642522 3082533446850352619311881710100031378387528865875332083 8142061717766914730359825349042875546873115956286388235 3787593751957781857780532171226806613001927876611195909 2164201989380952572010654858632788659361533818279682303 0195203530185296899577362259941389124972177528347913151 5574857242454150695950829533116861727855889075098381754 6374649393192550604009277016711390098488240128583616035 6370766010471018194295559619894676783744944825537977472 6847104047534646208046684259069491293313677028989152104 7521620569660240580381501935112533824300355876402474964 7326391419927260426992279678235478163600934172164121992 4586315030286182974555706749838505494588586926995690927 2107975093029553211653449872027559602364806654991198818 3479775356636980742654252786255181841757467289097777279 3800081647060016145249192173217214772350141441973568548 1613611573525521334757418494684385233239073941433345477 6241686251898356948556209921922218427255025425688767179 0494601653466804988627232791786085784383827967976681454 1009538837863609506800642251252051173929848960841284886 2694560424196528502221066118630674427862203919494504712 3713786960956364371917287467764657573962413890865832645 9958133904780275900994657640789512694683983525957098258 2262052248940772671947826848260147699090264013639443745 5305068203496252451749399651431429809190659250937221696 4615157098583874105978859597729754989301617539284681382 6868386894277415599185592524595395943104997252468084598 7273644695848653836736222626099124608051243884390451244 1365497627807977156914359977001296160894416948685558484 0635342207222582848864815845602850601684273945226746767 8895252138522549954666727823986456596116354886230577456 4980355936345681743241125150760694794510965960940252288 7971089314566913686722874894056010150330861792868092087 4760917824938589009714909675985261365549781893129784821 6829989487226588048575640142704775551323796414515237462 3436454285844479526586782105114135473573952311342716610 2135969536231442952484937187110145765403590279934403742 0073105785390621983874478084784896833214457138687519435 0643021845319104848100537061468067491927819119793995206 1419663428754440643745123718192179998391015919561814675 1426912397489409071864942319615679452080951465502252316 0388193014209376213785595663893778708303906979207734672 2182562599661501421503068038447734549202605414665925201 4974428507325186660021324340881907104863317346496514539 0579626856100550810665879699816357473638405257145910289 7064140110971206280439039759515677157700420337869936007 2305587631763594218731251471205329281918261861258673215 7919841484882916447060957527069572209175671167229109816 9091528017350671274858322287183520935396572512108357915 1369882091444210067510334671103141267111369908658516398 3150197016515116851714376576183515565088490998985998238 7345528331635507647918535893226185489632132933089857064 2046752590709154814165498594616371802709819943099244889 5757128289059232332609729971208443357326548938239119325 9746366730583604142813883032038249037589852437441702913 2765618093773444030707469211201913020330380197621101100 4492932151608424448596376698389522868478312355265821314 4957685726243344189303968642624341077322697802807318915 4411010446823252716201052652272111660396665573092547110 5578537634668206531098965269186205647693125705863566201 8558100729360659876486117910453348850346113657686753249 4416680396265797877185560845529654126654085306143444318 5867697514566140680070023787765913440171274947042056223 0538994561314071127000407854733269939081454664645880797 2708266830634328587856983052358089330657574067954571637 7525420211495576158140025012622859413021647155097925923 0990796547376125517656751357517829666454779174501129961 4890304639947132962107340437518957359614589019389713111 7904297828564750320319869151402870808599048010941214722 1317947647772622414254854540332157185306142288137585043 0633217518297986622371721591607716692547487389866549494 5011465406284336639379003976926567214638530673609657120 9180763832716641627488880078692560290228472104031721186 0820419000422966171196377921337575114959501566049631862 9472654736425230817703675159067350235072835405670403867 4351362222477158915049530984448933309634087807693259939 7805419341447377441842631298608099888687413260472156951 6239658645730216315981931951673538129741677294786724229 2465436680098067692823828068996400482435403701416314965 8979409243237896907069779422362508221688957383798623001 5937764716512289357860158816175578297352334460428151262 7203734314653197777416031990665541876397929334419521541 3418994854447345673831624993419131814809277771038638773 4317720754565453220777092120190516609628049092636019759 8828161332316663652861932668633606273567630354477628035 0450777235547105859548702790814356240145171806246436267 9456127531813407833033625423278394497538243720583531147 7119926063813346776879695970309833913077109870408591337 4641442822772634659470474587847787201927715280731767907 7071572134447306057007334924369311383504931631284042512 1925651798069411352801314701304781643788518529092854520 1165839341965621349143415956258658655705526904965209858 0338507224264829397285847831630577775606888764462482468 5792603953527734803048029005876075825104747091643961362 6760449256274204208320856611906254543372131535958450687 7246029016187667952406163425225771954291629919306455377 9914037340432875262888963995879475729174642635745525407 9091451357111369410911939325191076020825202618798531887 7058429725916778131496990090192116971737278476847268608 4900337702424291651300500516832336435038951702989392233 4517220138128069650117844087451960121228599371623130171 1444846409038906449544400619869075485160263275052983491 8740786680881833851022833450850486082503930213321971551 8430635455007668282949304137765527939751754613953984683 3936383047461199665385815384205685338621867252334028308 7112328278921250771262946322956398989893582116745627010 2183564622013496715188190973038119800497340723961036854 0664319395097901906996395524530054505806855019567302292 1913933918568034490398205955100226353536192041994745538 5938102343955449597783779023742161727111723643435439478 2218185286240851400666044332588856986705431547069657474 5855033232334210730154594051655379068662733379958511562 5784322988273723198987571415957811196358330059408730681 2160287649628674460477464915995054973742562690104903778 1986835938146574126804925648798556145372347867330390468 8383436346553794986419270563872931748723320837601123029 9113679386270894387993620162951541337142489283072201269 0147546684765357616477379467520049075715552781965362132 3926406160136358155907422020203187277605277219005561484 2555187925303435139844253223415762336106425063904975008 6562710953591946589751413103482276930624743536325691607 8154781811528436679570611086153315044521274739245449454 2368288606134084148637767009612071512491404302725386076 4823634143346235189757664521641376796903149501910857598 4423919862916421939949072362346468441173940326591840443 7805133389452574239950829659122850855582157250310712570 1266830240292952522011872676756220415420516184163484756 5169998116141010029960783869092916030288400269104140792 8862150784245167090870006992821206604183718065355672525 3256753286129104248776182582976515795984703562226293486 0034158722980534989650226291748788202734209222245339856 2647669149055628425039127577102840279980663658254889264 8802545661017296702664076559042909945681506526530537182 9412703369313785178609040708667114965583434347693385781 7113864558736781230145876871266034891390956200993936103 1029161615288138437909904231747336394804575931493140529 7634757481193567091101377517210080315590248530906692037 6719220332290943346768514221447737939375170344366199104 0337511173547191855046449026365512816228824462575916333 0391072253837421821408835086573917715096828874782656995 9957449066175834413752239709683408005355984917541738188 3999446974867626551658276584835884531427756879002909517 0283529716344562129640435231176006651012412006597558512 7617858382920419748442360800719304576189323492292796501 9875187212726750798125547095890455635792122103334669749 9235630254947802490114195212382815309114079073860251522 7429958180724716259166854513331239480494707911915326734 3028244186041426363954800044800267049624820179289647669 7583183271314251702969234889627668440323260927524960357 9964692565049368183609003238092934595889706953653494060 3402166544375589004563288225054525564056448246515187547 1196218443965825337543885690941130315095261793780029741 2076651479394259029896959469955657612186561967337862362 5612521632086286922210327488921865436480229678070576561 5144632046927906821207388377814233562823608963208068222 4680122482611771858963814091839036736722208883215137556 0037279839400415297002878307667094447456013455641725437 0906979396122571429894671543578468788614445812314593571 9849225284716050492212424701412147805734551050080190869 9603302763478708108175450119307141223390866393833952942 5786905076431006383519834389341596131854347546495569781 0382930971646514384070070736041123735998434522516105070 2705623526601276484830840761183013052793205427462865403 6036745328651057065874882256981579367897669742205750596 8344086973502014102067235850200724522563265134105592401 9027421624843914035998953539459094407046912091409387001 2645600162374288021092764579310657922955249887275846101 2648369998922569596881592056001016552563756785667227966 1988578279484885583439751874454551296563443480396642055 7982936804352202770984294232533022576341807039476994159 7915945300697521482933665556615678736400536665641654732 1704390352132954352916941459904160875320186837937023488 8689479151071637852902345292440773659495630510074210871 4261349745956151384987137570471017879573104229690666702 1449863746459528082436944578977233004876476524133907592 0434019634039114732023380715095222010682563427471646024 3354400515212669324934196739770415956837535551667302739 0074972973635496453328886984406119649616277344951827369 5588220757355176651589855190986665393549481068873206859 9075407923424023009259007017319603622547564789406475483 4664776041146323390565134330684495397907090302346046147 0961696886885014083470405460742958699138296682468185710 3188790652870366508324319744047718556789348230894310682 8702722809736248093996270607472645539925399442808113736 9433887294063079261595995462624629707062594845569034711 9729964090894180595343932512362355081349490043642785271 3831591256898929519642728757394691427253436694153236100 4537304881985517065941217352462589548730167600298865925 7866285612496655235338294287854253404830833070165372285 6355915253478445981831341129001999205981352205117336585 6407826484942764411376393866924803118364453698589175442 6473998822846218449008777697763127957226726555625962825 4276531830013407092233436577916012809317940171859859993 3849235495640057099558561134980252499066984233017350358 0440811685526531170995708994273287092584878944364600504 1089226691783525870785951298344172953519537885534573742

  6. Lady Fitzgerald

    Some of the capchas I’ve run into are bloody well impossible to read and won’t cut me any slack. Others let me put in ?? and get away with it.

  7. stephen surls

    im almost blind and the ‘play this captcha’ is no help either.

  8. Mike

    The concept of Capchas is good but the execution sucks. It’s NOT that hard to screw up text recognition.
    They could make it easier for a human to read without adding all the cute colored ribbons and twists and turns that cause repeated attempts without success.

  9. Deez

    If I see a formula, I just hit the Refresh button and get actual words. Done.

  10. trm96

    I have seen some captchas that required you to type only certain charters that is displayed (ie type charters 1, 6 7,9 or only type the blue charters), also ones that make you do math to solve them.

  11. Teer

    Some sites like Facebook and twitter have made captchas such that they are actually scanned portions of huge antiques texts which the computer cannot decode by itself. So every time many people type in the same text for a particular captcha, that is what the scanned image is translated as in a large online database of old texts.

    So the next time you fill in a captcha, remember that you are doing your bit towards conserving your heritage.

  12. Balachander

    How to secure a website with captcha alone without any password ?
    Give this as the Captcha
    *****

  13. BAF

    @Teer – that’s what recaptcha is/does.

  14. Meow

    I can never get these to work. How do you type the letters all slanted and squiggly?

  15. Chris

    Someone got a cow once, how do you type a cow? O_o;

  16. Kiss

    I can see your bank account password =)

  17. ejes

    no problem:

    e²/4πεoc≈ ssofPr

    √gd4x rtailhi

Enter Your Email Here to Get Access for Free:

Go check your email!