53 Handy A/B & Multivariate Testing Tools:

8Seconds Real Time Image Optimizer
AB Tasty
Accenture Digital Optimization
AdBean
Adobe Test & Target powered by Omniture
Amadesa
Autonomy Optimost
Avenseo
Baynote Optimization Center
BoostCTR
Celebrus Technologies
Cognesia
Conversion Multiplier
Convert Experiments
Ektron Marketing Optimization
Experimently
EyeView
Flashvariations
Get Smart Content
GlobalMaxer
Google Content Experiments (Formerly Google Website Optimizer)
Hiconversion
Informz (Email Testing)
Insegment
Kameleoon
ion interactive 
Liwio
Marketing Optimizer
Marketo
Maxymiser
Monetate (Gold Listing)
Optimizely
Padiact
Personyze
Pluralis
Pure360
RedEye, Inc.
Silverpop
SiteSpect (Platinum Listing)
SparkPage
Split Test Accelerator
TuningEngine by SiteTuners
Unbounce
Unica Interactive Marketing
Vertster
Visual Website Optimizer
Webtrends Optimize
Xander.io
Zentester

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