Regex tester
Test regular expressions with live highlighting.
- Developer
- Free to use
- Server processed
Your input
Set your options
Run Regex Tester
Processed on our servers. Sent over TLS, and any file it makes is deleted an hour later — 24 hours if you are signed in.
Type or paste your input above to run this tool.
Three steps
How to use Regex Tester
- Step 01
Pick your input
Paste your text into the box above.
- Step 02
Configure & run
Adjust the options (pattern, flags) and click Run. The work runs on our own infrastructure — no third-party processing APIs in the path.
- Step 03
Download the result
A JSON document is downloadable below.
This tool runs on our servers. There is nothing to upload, and any file it makes is deleted an hour after it is made — 24 hours if you are signed in. We do not use third-party processing APIs.
About Regex Tester
Build and test regular expressions interactively. It sits in the developer shelf alongside 76 other developer tools, needs no account, and keeps the same behaviour whether you open it here or call it through the REST API.
It works from what you type in rather than a file and gives back JSON. The work happens on our servers. There is nothing to upload, and any file it makes is deleted an hour later — 24 hours if you are signed in. The same operation is available programmatically at POST /v1/dev/regex.
Regex Tester questions
Where does Regex Tester do its work?
On our own servers. There is no file to upload: what you enter is sent over TLS and processed on our infrastructure — no third-party processing APIs are in the path — and any file it makes is deleted within an hour.
Do I need an account to use Regex Tester?
No. Regex Tester works without signing in, and that is not a trial — it is how the free tier works. An account only matters for things that need one to exist at all: larger server jobs against your quota, API keys, saved workflows and billing.
Can I run Regex Tester from my own code?
Yes. Every tool on the site is reachable from the REST API with the same slug — `regex-test` — and the same options as this page, so anything you can do here you can automate.