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Cookie Size and its Expiration Time

alexbdp 06-16-16
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Cookie Size and its Expiration Time

Hi all,


I have read that the optimizelyEndUserId and optimizelyBuckets cookies have an expiration time of 10 years. What is the maximum size of optimizelyByckets's cookie can achieve? If I pause a experiment, my user will still have cookie in his browser? I need to archive it to eliminate it?

Currently, my website's cookie limit is 4k and I want to optmize my cookies and to know how many experiments can I run at the same time. 

Thanks in advance,

Level 1

robertchan 06-17-16

Re: Cookie Size and its Expiration Time

To reset cookies, it's recommended to duplicate and restart your experiment or create a completely new one. Once an experiment starts, a visitor will be bucketed into the same variant he or she was originally sent to. You can run multiple experiments at the same time by checking if a user has a certain cookie or not.
Robert Chan

Experimentation Hero
alexbdp 06-17-16

Re: Cookie Size and its Expiration Time

Thank you, Robert!

But, what I really wanna know is how big is the cookies that my visitor bucketed will have if he has been bucketed for a lot of experiments.
I want to optimize that and have a small cookie size from optimizely. If I archive or pause my experiment, the cookie will expire for my visitor or not?
I know that if I pause a varition, the visitor bucked will still see the variation.

I'm having problems because my currently cookies size is very big.

Level 1
beckyhall 06-17-16

Re: Cookie Size and its Expiration Time

Hey Alex,


The Optimizely cookie will definitely grow with ever experiment that user is included in. You can exclude draft and paused experiments from the cookie in the settings section, but this will also not allow you to use force parameters to preview tests that are not currently running.