Troubleshooting and FAQ

Troubleshooting#

assigned is always false#

• The experiment is not Running. Drafts, paused and completed experiments never assign.
• Traffic allocation is below 100% and this visitor is outside it. Try a private window, or set allocation to 100% while testing.
• The organization hit its monthly visitor limit. The response then includes "reason": "quota_exceeded".

401 Missing or invalid API key#

The key is missing, mistyped, or not an SDK key. Browser calls need a cro_pk_... key. Copying the key with extra spaces is a common cause.

401 Unknown or revoked API key#

The key was revoked or copied incorrectly. Create a new one on the API keys page.

404 Experiment not found#

The experiment ID is wrong, or the key belongs to a different project than the experiment. Keys and experiments must be in the same project.

403 This account is suspended#

Your organization's account has been suspended. Contact support.

429 Rate limit exceeded#

Too many requests from one key and IP in a minute. This usually means a loop calling getVariation with a fresh page each time, or load testing from one machine. Wait for the Retry-After seconds.

Conversions are not recorded#

Look for [ABTest] No assignment found in the console. trackConversion needs run or getVariation to have been called for that experiment on the same page load first. See the SDK reference.

The same person sees different variations#

Generated visitor IDs live in localStorage, so a different browser, device, private window or cleared storage means a new visitor. Pass your own userId to init for logged-in users.

The original content flashes before the variant#

Load the snippet in the <head> and use the anti-flicker pattern.

Starting an experiment says the monthly limit is reached#

Your organization's plan has a monthly experiment start limit. Resuming paused experiments still works. Contact support to raise the limit.

FAQ#

Why do I see "Complete your profile to create experiments"?#

Creating or starting a test needs your first name, last name and country. Open Profile in the sidebar, fill them in and save, and you go straight back to where you were. Everything else on the profile is optional, and the dashboard, docs and settings work without it.

Do I need to write code?#

A few lines. You add the snippet and write the change for each variation in JavaScript. A visual editor is on the roadmap.

Will it slow my site down?#

The script is about 15 KB gzipped and loads asynchronously. It makes one small request on page load.

Which statistics do you use?#

A two-sided two-proportion z-test of the best variant against the control, at 95% confidence, and Wilson score intervals for each conversion rate. See Reading results.

Can I change variations after starting?#

You can change the traffic split, pause a variation, change who can enter and add goals from the Edit test tab. Those changes apply to new visitors only. Variation URLs cannot change and variations cannot be added or removed, so results stay valid. For different pages, create a new test.

What are the free plan limits?#

The free plan includes 10,000 tested visitors a month and up to 300 a day, 1 running test at a time, 10 tests over the life of the account, 1 project on 1 domain, and A/B tests with a control plus 1 variation. Subdomains count as the same domain, a domain can be on one free account at a time, and each domain gets 10 free tests in total. A test counts once you start it, and deleting it does not give it back. Past the visitor limits, new visitors see your original page and are not counted, while visitors already in a test keep their version. Your usage is on the Overview page.

What happens when I reach my monthly pageview limit?#

Paid plans include a number of tracked pageviews a month. A tracked pageview is a page load on a control or variation page of a running test. Other pages do not count. Your usage is on the Overview page. When you reach the limit, tests pause until the 1st of next month (UTC): visitors see your original pages, nothing is redirected and no new data is collected. You are never charged for going over. Upgrade for a higher limit.

Where is my data stored?#

In our secure database. Each organization's data is kept separate, and each environment's results are kept apart.

Is there a WordPress plugin, GA4 integration or React package?#

Not yet. The script tag works on any site today. See Install guides for Google Tag Manager and WordPress.

Is it really free?#

There is a free plan and no billing system yet. Pricing for larger plans has not been set.