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Don’tMakeMeThink,Revisited
ACommonSenseApproachtoWebUsability

SteveKrug


Don’tMakeMeThink,Revisited
ACommonSenseApproachtoWebUsability
Copyright©2014SteveKrug
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hardwareproductsdescribedinit.
Trademarks
It’snotrocketsurgery™isatrademarkofSteveKrug.
Manyofthedesignationsusedbymanufacturersandsellerstodistinguishtheirproductsareclaimedas
trademarks.Wherethosedesignationsappearinthisbook,andPeachpitwasawareofatrademark
claim,thedesignationsappearasrequestedbytheownerofthetrademark.Allotherproductnamesand
servicesidentifiedthroughoutthisbookareusedineditorialfashiononlyandforthebenefitofsuch
companieswithnointentionofinfringementofthetrademark.Nosuchuse,ortheuseofanytrade
name,isintendedtoconveyendorsementorotheraffiliationwiththisbook.
ISBN-13:978-0-321-96551-6
ISBN-10:0-321-96551-5
987654321
PrintedandboundintheUnitedStatesofAmerica


FirstEdition
Tomyfather,whoalwayswantedmetowriteabook,
Mymother,whoalwaysmademefeellikeIcould,
Melanie,whomarriedme—thegreateststrokeofgoodfortuneofmylife,
andmyson,Harry,whowillsurelywritebooksmuchbetterthanthisonewheneverhewantsto.

SecondEdition
Tomybigbrother,Phil,whowasamenschhiswholelife.

ThirdEdition
Toallthepeople—fromallpartsoftheworld—whohavebeensoniceaboutthisbookforfourteen
years.Yourkindwords—inperson,inemail,andinyourblogs—havebeenoneofthegreatjoysofmy
life.
Especiallythewomanwhosaiditmadeherlaughsohardthatmilkcameoutofhernose.

Contents
PREFACEAboutthisedition
INTRODUCTIONReadmefirst
Throatclearinganddisclaimers
GUIDINGPRINCIPLES
CHAPTER1Don’tmakemethink!
Krug’sFirstLawofUsability
CHAPTER2HowwereallyusetheWeb
Scanning,satisficing,andmuddlingthrough
CHAPTER3BillboardDesign101
Designingforscanning,notreading
CHAPTER4Animal,Vegetable,orMineral?
Whyuserslikemindlesschoices
CHAPTER5Omit

words

TheartofnotwritingfortheWeb
THINGSYOUNEEDTOGETRIGHT
CHAPTER6StreetsignsandBreadcrumbs
Designingnavigation
CHAPTER7TheBigBangTheoryofWebDesign
Theimportanceofgettingpeopleoffontherightfoot
MAKINGSUREYOUGOTTHEMRIGHT
CHAPTER8“TheFarmerandtheCowmanShouldBeFriends”
Whymostargumentsaboutusabilityareawasteoftime,andhowtoavoidthem
CHAPTER9Usabilitytestingon10centsaday
Keepingtestingsimple—soyoudoenoughofit
LARGERCONCERNSANDOUTSIDEINFLUENCES

CHAPTER10Mobile:It’snotjustacityinAlabamaanymore
Welcometothe21stCentury.Youmayexperienceaslightsenseofvertigo
CHAPTER11Usabilityascommoncourtesy
WhyyourWebsiteshouldbeamensch


CHAPTER12Accessibilityandyou
Justwhenyouthinkyou’redone,acatfloatsbywithbutteredtoaststrappedtoitsback
CHAPTER13Guidefortheperplexed
Makingusabilityhappenwhereyoulive
Acknowledgments
Index


Preface:Aboutthisedition
Peoplecomeandgosoquicklyhere!
—DOROTHYGALE(JUDYGARLAND)INTHEWIZARDOFOZ(1939)

IwrotethefirsteditionofDon’tMakeMeThinkbackin2000.
By2002,Ibegantogetafewemailsayearfromreadersasking(verypolitely)ifI’dthoughtabout
updatingit.Notcomplaining;justtryingtobehelpful.“Alotoftheexamplesareoutofdate”wasthe
usualcomment.
MystandardresponsewastopointoutthatsinceIwroteitrightaroundthetimetheInternetbubble
burst,manyofthesitesIusedasexampleshadalreadydisappearedbythetimeitwaspublished.ButI
didn’tthinkthatmadetheexamplesanylessclear.
Finally,in2006Ihadastrongpersonalincentivetoupdateit.1ButasIrereadittoseewhatIshould
change,Ijustkeptthinking“Thisisallstilltrue.”Ireallycouldn’tfindmuchofanythingthatIthought
shouldbechanged.
1Halfoftheroyaltiesforthebookweregoingtoacompanythatnolongerexisted,anddoinganeweditionmeantanewcontract—
andtwicetheroyalties—forme.

Ifitwasanewedition,though,somethinghadtobedifferent.SoIaddedthreechaptersthatIdidn’t
havetimetofinishbackin2000,hitthesnoozebutton,andhappilypulledthecoversbackovermy
headforanothersevenyears.

2000


2006
(Writingisreallyhardforme,andI’malwayshappytohaveareasonnottodoit.Givemeagoodold
rootcanaloverwritinganyday.)
Sowhynow,finally,anewedition?Tworeasons.

#1.Let’sfaceit:It’sold
There’snodoubtaboutitatthispoint:Itfeelsdated.Afterall,it’sthirteenyearsold,whichislikea
hundredyearsinInternettime.(See?Nobodyevensaysthingslike“inInternettime”anymore.)
MostoftheWebpagesIusedforexamples,likeSenatorOrrinHatch’scampaignsiteforthe2000
election,lookreallyold-fashionednow.
Sitesthesedaystendtolookalotmoresophisticated,asyoumightexpect.


www.orrinhatch.com1999


www.orrinhatch.com2012
RecentlyI’vebeenstartingtoworrythatthebookwouldfinallyreachapointwhereitfeltsodatedthat
itwouldstopbeingeffective.Iknowithasn’thappenedyetbecause
It’sstillsellingsteadily(thankheavens),withoutanysignofslowingdown.It’sevenbecome
requiredreadinginalotofcourses,somethingIneverexpected.
Newreadersfromallovertheworldcontinuetotweetaboutthingsthey’velearnedfromit.

Istillkeephearingthisstory:“Igaveittomyboss,hopinghe’dfinallyunderstandwhatI’m
talkingabout.Heactuallyreadit,andthenheboughtitforourwholeteam/department/company!”


(Ilovethatstory.)
Peoplekeeptellingmethattheygottheirjobthanksinparttoreadingitorthatitinfluencedtheir
choiceofacareer.2
2I’menormouslypleasedandflattered,butIhavetoadmitthere’salwaysapartofmethat’sthinking“Yikes!Ihopeshewasn’tmeant
tobeabrainsurgeon.WhathaveIdone?”

ButIknowthateventuallytheagingeffectisgoingtokeeppeoplefromreadingit,forthesamereason
thatitwassohardtogetmysontowatchblackandwhitemovieswhenhewasyoung,nomatterhow
goodtheywere.
Clearly,it’stimefornewexamples.

#2.Theworldhaschanged
TosaythatcomputersandtheInternetandthewayweusethemhavechangedalotlatelyisputtingit
mildly.Verymildly.

Thelandscapehaschangedinthreeways:
Technologygotitshandsonsomesteroids.In2000,wewereusingtheWebonrelativelylarge
screens,withamouseortouchpadandakeyboard.Andweweresittingdown,oftenatadesk,
whenwedid.
Nowweusetinycomputersthatwecarryaroundwithusallthetime,withstillandvideo
cameras,magicalmapsthatknowexactlywhereweare,andourentirelibrariesofbooksand
musicbuiltin.AndarealwaysconnectedtotheInternet.Oh,andthey’rephones,too.
Heck,Icanusemy“phone”to

...bookarestaurantreservationinseconds


...adjusttheheatinmyhousefromanywhere


...ordepositacheckwithoutgoingtoanATM
It’snoflyingcar(which,cometothinkofit,wewerepromisedwe’dhavebynow),butit’spretty
impressive.
TheWebitselfkeptimproving.EvenwhenI’musingmydesktopcomputertodoallthethings
I’vealwaysdoneontheWeb(buyingstuff,makingtravelplans,connectingwithfriends,reading
thenews,andsettlingbarbets),thesitesIusetendtobemuchmorepowerfulandusefulthan
theirpredecessors.
We’vecometoexpectthingslikeautosuggestandautocorrect,andwe’reannoyedwhenwecan’t
payaparkingticketorrenewadriver’slicenseonline.

Usabilitywentmainstream.In2000,notthatmanypeopleunderstoodtheimportanceof
usability.
Now,thanksinlargeparttoSteveJobs(andJonathanIve),almosteveryoneunderstandsthatit’s
important,evenifthey’restillnotentirelysurewhatitis.ExceptnowtheyusuallycallitUser


ExperienceDesign(UXDorjustUX),anumbrellatermforanyactivityorprofessionthat
contributestoabetterexperiencefortheuser.
It’sgreatthatthere’snowsomuchmoreemphasisondesigningfortheuser,butallthenewjob
descriptions,subspecialties,andtoolsthathavecomealongwiththisevolutionhaveleftalotof
peopleconfusedaboutwhattheyshouldactuallydoaboutit.
I’llbetalkingaboutallthreeofthesechangesthroughoutthebook.

Don’tgetmewrong...

Thiseditionhasnewexamples,somenewprinciples,andafewthingsI’velearnedalongtheway,but
it’sstillthesamebook,withthesamepurpose:It’sstillabookaboutdesigninggreat,usableWebsites.
Andit’salsostillabookaboutdesigninganythingthatpeopleneedtointeractwith,whetherit’sa
microwaveoven,amobileapp,oranATM.
Thebasicprinciplesarethesameevenifthelandscapehaschanged,becauseusabilityisaboutpeople
andhowtheyunderstandandusethings,notabouttechnology.Andwhiletechnologyoftenchanges
quickly,peoplechangeveryslowly.3
3There’sawonderfulNorwegianvideo(withsubtitles)aboutthisthatshowsamonkgettinghelpashestrugglestousethenewfangled
“book.”(Searchfor“medievalhelpdesk”onYouTube.)

OrasJakobNielsensoaptlyputit:
Thehumanbrain’scapacitydoesn’tchangefromoneyeartothenext,sotheinsightsfrom
studyinghumanbehaviorhaveaverylongshelflife.Whatwasdifficultforuserstwentyyears
agocontinuestobedifficulttoday.
Ihopeyouenjoythenewedition.Anddon’tforgettowaveinafewyearswhenyoupassmeinyour
flyingcar.
STEVEKRUG
NOVEMBER2013


Introduction:Readmefirst
THROATCLEARINGANDDISCLAIMERS
Ican’ttellyouanythingyoudon’talreadyknow.ButI’dliketoclarifyafewthings.
—JOEFERRARA,AHIGHSCHOOLFRIENDOFMINE

Ihaveagreatjob.I’mausabilityconsultant.Here’swhatIdo:
People(“clients”)sendmesomethingthey’reworkingon.
ItcouldbedesignsforanewWebsitethey’rebuilding,ortheURLofasitethatthey’re
redesigning,oraprototypeofanapp.

Itryusingwhattheysendme,doingthethingsthattheiruserswouldneedorwanttodowithit.I
notetheplaceswherepeoplearelikelytogetstuckandthethingsthatIthinkwillconfusethem
(an“expertusabilityreview”).
SometimesIgetotherpeopletotryusingitwhileIwatchtoseewheretheygetstuckand
confused(“usabilitytesting”).


Ihaveameetingwiththeclient’steamtodescribetheproblemsIfoundthatarelikelytocause
usersgrief(“usabilityissues”)andhelpthemdecidewhichonesaremostimportanttofixand
howbesttofixthem.

Sometimesweworkbythephone...

...andsometimesinperson
IusedtowritewhatIcalledthe“bighonkingreport”detailingmyfindings,butIfinallyrealized
thatitwasn’tworththetimeandeffort.Alivepresentationallowspeopletoaskmequestionsand
voicetheirconcerns—somethingawrittenreportdoesn’tdo.AndforteamsdoingAgileorLean


development,there’snotimeforwrittenreportsanyway.
Theypayme.
Beingaconsultant,Igettoworkoninterestingprojectswithalotofnice,smartpeople.Igettoworkat
homemostofthetimeandIdon’thavetositinmind-numbingmeetingseverydayordealwithoffice
politics.IgettosaywhatIthink,andpeopleusuallyappreciateit.AndIgetpaidwell.
Ontopofallthat,Igetalotofjobsatisfaction,becausewhenwe’refinished,thethingsthey’rebuilding
arealmostalwaysmuchbetterthanwhenwestarted.1
1Almostalways.Evenwhenpeopleknowaboutusabilityproblems,theycan’talwaysfixthemcompletely,asI’llexplaininChapter9.

Thebadnews:Youprobablydon’thaveausabilityprofessional

Almosteverydevelopmentteamcouldusesomebodylikemetohelpthembuildusabilityintotheir
products.Unfortunately,thevastmajorityofthemcan’taffordtohireausabilityprofessional.
Andeveniftheycould,therearen’tenoughtogoaround.AtlastcounttherewereumpteenbillionWeb
sites(andumpteenbillionappsfortheiPhonealone2)andonlyabout10,000usabilityconsultants
worldwide.Youdothemath.
2I’mnotquitesurewhyApplebragsaboutthis.Havingthousandsofgoodappsforaplatformisareallygoodthing.Havingmillions
ofmediocreappsjustmeansit’sreallyhardtofindthegoodones.

Andevenifyoudohaveaprofessionalonyourteam,thatpersoncan’tpossiblylookateverythingthe
teamproduces.
Inthelastfewyears,makingthingsmoreusablehasbecomealmosteverybody’sresponsibility.Visual
designersanddevelopersnowoftenfindthemselvesdoingthingslikeinteractiondesign(decidingwhat
happensnextwhentheuserclicks,taps,orswipes)andinformationarchitecture(figuringouthow
everythingshouldbeorganized).
Iwrotethisbookmainlyforpeoplewhocan’taffordtohire(orrent)someonelikeme.
Knowingsomeusabilityprincipleswillhelpyouseetheproblemsyourself—andhelpkeepyoufrom
creatingtheminthefirstplace.
Noquestion:Ifyoucanaffordto,hiresomeonelikeme.Butifyoucan’t,Ihopethisbookwillenable
youtodoityourself(inyourcopioussparetime).

Thegoodnews:It’snotrocketsurgery™
Fortunately,muchofwhatIdoisjustcommonsense,andanyonewithsomeinterestcanlearntodoit.
Likealotofcommonsense,though,it’snotnecessarilyobviousuntilaftersomeone’spointeditoutto
you.3
3...whichisonereasonwhymyconsultingbusinessiscalledAdvancedCommonSense.“It’snotrocketsurgery”ismycorporate
motto.

Ispendalotofmytimetellingpeoplethingstheyalreadyknow,sodon’tbesurprisedifyoufind
yourselfthinking“Iknewthat”alotinthepagesahead.

©2013.TheNewYorkerCollectionfromcartoonbank.comAllRightsReserved.

It’sathinbook
Moregoodnews:I’veworkedhardtokeepthisbookshort—hopefullyshortenoughsoyoucanreadit
onalongplaneride.Ididthisfortworeasons:

Ifit’sshort,it’smorelikelytoactuallybeused.4I’mwritingforthepeoplewhoareinthe
trenches—thedesigners,thedevelopers,thesiteproducers,theprojectmanagers,themarketing
people,andthepeoplewhosignthechecks—andfortheone-man-bandswhoaredoingitall
themselves.
4There’sagoodusabilityprinciplerightthere:Ifsomethingrequiresalargeinvestmentoftime—orlookslikeitwill—it’slesslikelyto
beused.

Usabilityisn’tyourlife’swork,andyoudon’thavetimeforalongbook.
Youdon’tneedtoknoweverything.Aswithanyfield,there’salotyoucouldlearnabout
usability.Butunlessyou’reausabilityprofessional,there’salimittohowmuchisusefulforyou
tolearn.5
5I’vealwayslikedthepassageinAStudyinScarletwhereDr.WatsonisshockedtolearnthatSherlockHolmesdoesn’tknowthatthe
earthtravelsaroundthesun.Giventhefinitecapacityofthehumanbrain,Holmesexplains,hecan’taffordtohaveuselessfacts
elbowingouttheusefulones:


“Whatthedeuceisittome?Yousaythatwegoroundthesun.Ifwewentroundthemoonitwouldnotmakeapennyworthof
differencetomeortomywork.”

IfindthatthemostvaluablecontributionsImaketoeachprojectalwayscomefromkeepingjustafew
keyusabilityprinciplesinmind.Ithinkthere’salotmoreleverageformostpeopleinunderstanding
theseprinciplesthaninanotherlaundrylistofspecificdo’sanddon’ts.I’vetriedtoboildownthefew
thingsIthinkeverybodyinvolvedindesignshouldknowaboutusability.

Notpresentattimeofphoto
Justsoyoudon’twasteyourtimelookingforthem,hereareafewthingsyouwon’tfindinthisbook:
Hardandfastusabilityrules.I’vebeenatthisforalongtime,longenoughtoknowthatthereis
noone“right”answertomostusabilityquestions.Designisacomplicatedprocessandthereal
answertomostofthequestionspeopleaskmeis“Itdepends.”ButIdothinkthatthereareafew
usefulguidingprinciplesitalwayshelpstohaveinmind,andthosearewhatI’mtryingtoconvey.
PredictionsaboutthefutureoftechnologyandtheWeb.Honestly,yourguessisasgoodas
mine.TheonlythingI’msureofisthat(a)mostofthepredictionsIheararealmostcertainly
wrong,and(b)thethingsthatwillturnouttobeimportantwillcomeasasurprise,eventhoughin
hindsightthey’llseemperfectlyobvious.
Bad-mouthingofpoorlydesignedsitesandapps.Ifyouenjoypeoplepokingfunatthingswith
obviousflaws,you’rereadingthewrongbook.Designing,building,andmaintainingagreatWeb
siteorappisn’teasy.It’slikegolf:ahandfulofwaystogettheballinthehole,amillionwaysnot
to.Anyonewhogetsitevenhalfrighthasmyadmiration.
Asaresult,you’llfindthattheexamplesIusetendtobefromexcellentproductswithminor
flaws.Ithinkyoucanlearnmorefromlookingatgooddesignsthanbadones.

NowwithMobile!
OneofthedilemmasIfacedwhenupdatingthisbookwasthatit’salwaysbeenabookaboutdesigning
usableWebsites.Eventhoughtheprinciplesapplytothedesignofanythingpeoplehavetointeract
with(includingthingslikeelectionballotsandvotingbooths,andevenPowerPointpresentations),its
focuswasclearlyonWebdesign,andalltheexampleswerefromWebsites.Untilrecently,that’swhat
mostpeoplewereworkingon.
Butnowtherearealotofpeopledesigningmobileapps,andeventhepeopleworkingonWebsites
havetocreateversionsofthemthatworkwellonmobiledevices.Iknowthey’reveryinterestedinhow
allofthisappliestothem.
SoIdidthreethings:
Includedmobileexampleswhereveritmadesense
Addedanewchapteraboutsomemobile-specificusabilityissues

Andthemostimportantone:Added“andMobile”tothesubtitleonthecover
Andasyou’llsee,insomeplaceswhereitmadethingsclearer,insteadof“Website”I’vewritten“Web
siteormobileapp.”Inmostcases,though,IusedtheWeb-centricwordingtokeepthingsfromgetting
cumbersomeanddistracting.

Onelastthing,beforewebegin
Onecrucialthing,really:Mydefinitionofusability.
You’llfindalotofdifferentdefinitionsofusability,oftenbreakingitdownintoattributeslike


Useful:Doesitdosomethingpeopleneeddone?
Learnable:Canpeoplefigureouthowtouseit?
Memorable:Dotheyhavetorelearniteachtimetheyuseit?
Effective:Doesitgetthejobdone?
Efficient:Doesitdoitwithareasonableamountoftimeandeffort?
Desirable:Dopeoplewantit?
andrecentlyeven
Delightful:Isusingitenjoyable,orevenfun?
I’lltalkabouttheselater.Buttome,theimportantpartofthedefinitionisprettysimple.Ifsomethingis
usable—whetherit’saWebsite,aremotecontrol,orarevolvingdoor—itmeansthat
Apersonofaverage(orevenbelowaverage)abilityandexperiencecanfigureouthowtouse
thethingtoaccomplishsomethingwithoutitbeingmoretroublethanit’sworth.
Takemywordforit:It’sreallythatsimple.
Ihopethisbookwillhelpyoubuildbetterproductsand—ifitletsyouskipafewoftheendless
argumentsaboutdesign—maybeevengethomeintimefordinneronceinawhile.


GuidingPrinciples

Chapter1.Don’tmakemethink!
KRUG’SFIRSTLAWOFUSABILITY
Michael,whyarethedrapesopen?
—KAYCORLEONEINTHEGODFATHER,PARTII

Peopleoftenaskme:
“What’sthemostimportantthingIshoulddoifIwanttomakesuremysiteorappiseasyto
use?”
Theanswerissimple.It’snot“Nothingimportantshouldeverbemorethantwoclicksaway”or“Speak
theuser’slanguage”or“Beconsistent.”
It’s...

“Don’tmakemethink!”
ForaslongIcanremember,I’vebeentellingpeoplethatthisismyfirstlawofusability.
It’stheoverridingprinciple—theultimatetiebreakerwhendecidingwhetheradesignworksorit
doesn’t.Ifyouhaveroominyourheadforonlyoneusabilityrule,makethistheone.
Forinstance,itmeansthatasfarasishumanlypossible,whenIlookataWebpageitshouldbeselfevident.Obvious.Self-explanatory.
Ishouldbeableto“getit”—whatitisandhowtouseit—withoutexpendinganyeffortthinkingabout
it.
Justhowself-evidentarewetalkingabout?
Well,self-evidentenough,forinstance,thatyournextdoorneighbor,whohasnointerestinthesubject
ofyoursiteandwhobarelyknowshowtousetheBackbutton,couldlookatyourHomepageandsay,
“Oh,it’sa_____.”(Withanyluck,she’llsay,“Oh,it’sa_____.Great!”Butthat’sanothersubject.)
Thinkofitthisway:
WhenI’mlookingatapagethatdoesn’tmakemethink,allthethoughtballoonsovermyheadsay
thingslike“OK,there’sthe_____.Andthat’sa_____.Andthere’sthethingthatIwant.”


NotThinking

ButwhenI’mlookingatapagethatmakesmethink,allthethoughtballoonsovermyheadhave
questionmarksinthem.
Thinking

Whenyou’recreatingasite,yourjobistogetridofthequestionmarks.