# Trials

Trials are useful when you want to give your customers some time to try your product before you start charging them. Be it 7 or 30 days, or 6 months, you decide how and when to charge them.

The duration of a trial is defined in the API request in the trial_days key. For example, a request to create a subscription with a 30-day trial would contain the following in the request body:

  "trial_days": 30

Read more about declaring trial periods in a sample scenario of creating a subscription with a trial or in APIref: Plans(opens new window) .