HMAC Signature Tester
Compute a webhook HMAC over a payload and compare it against the signature you were sent.
Other free tools
Start Free — no credit card
The free plan includes 1,000 links, 6 custom domains and 50,000 tracked clicks a month, free forever. Choose a free subdomain from six shared domains. Paid plans start at $4 a month when you outgrow it, and you keep everything you have built.
Frequently asked questions
Is HMAC Signature Tester free?
Yes. HMAC Signature Tester is free to use and needs no account. A fair-use rate limit applies per address so the tool stays available for everyone.
What does HMAC Signature Tester do?
Compute a webhook HMAC over a payload and compare it against the signature you were sent.. It is one of the free developers tools ShortFreeURL publishes; the full list is on the tools page.
Do I need to sign up or install anything?
No. Open the page and use it. An account is only needed if you want to keep, edit or measure the links you create — that is what the ShortFreeURL dashboard is for.
Can I use it on a phone?
Yes. Every tool on the site works in a mobile browser as well as on a desktop.