Verify people without asking for their ID
One API call with their Check Twice link returns who they are.
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Easy identity verification for your agent, shop or app
Know exactly who you’re dealing with
Make sure it’s still them
Common developer questions
Sign up to create a workspace on check-twice.com, then create API keys in your workspace.
Nothing. It’s free, with tiers and rate limits in place to stop abuse.
Yes. They make their link in the Check Twice app after proving who they are with a quick photo and their ID. It’s free for them too.
Make a link in the Check Twice app yourself and check it with your own key.
Whoever makes a link can see each time it’s opened, and whether a person or a system opened it. They can also choose how many times it opens, from once to unlimited, so it can’t be reused.
Yes. Each check returns a code for the person who made the link. Their links always give you the same code, so you’ll know when it’s them again. Anyone else checking gets a different one.
No. It must only be used to verify who they are, never stored, copied or shared.
You get “link_not_valid” if it was deleted or never existed. Just ask them to generate a new one.
Keep it on your server, never in a browser or an app. If it’s ever exposed, delete it and make a new one.