Regex101
Builds a regular expression while explaining every token in a side panel and highlighting matches as you type. Ends a lot of guessing.
Opens in a new tab. We do not control this site and it may have changed since we catalogued it.
How to get the most from it
Regex101 sits in Unreasonably Useful under Learn, filed as coffee break.
- Set aside five to fifteen minutes and give it your proper attention.
- Use a laptop or desktop computer — we file it as desktop only.
- It works with the sound off, so it is fine on a train or in a quiet office.
- No account needed — you can start without signing up.
- Go in expecting something useful and brainy.
About this category: Sites that quietly do a job you would otherwise pay for or install software for. Included because being this good for free is genuinely strange.
Good for
- Filling a coffee break properly
- Getting something practical done
- Giving your brain a workout
- A quiet break at your desk
- Trying it with zero commitment
Regex101: quick answers
Is Regex101 free?
Yes. Regex101 is free to use and needs no account.
Do I need an account to use Regex101?
No. You can use Regex101 without signing up for anything.
Does Regex101 work on a phone?
Not well. We file Regex101 as desktop only, so open it on a laptop or desktop computer.
Is Regex101 safe for work?
Yes, we file it as safe for work. It also works muted.
How long does Regex101 take?
We file it as "Coffee break": Five to fifteen minutes of proper attention.
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