regex tester

Regex Tester

Test a regex pattern against sample text, review matches, positions and capture groups directly in the browser.

Runs locally in your browser No uploads Instant results

Best for

Regex Tester is strongest for fast developer work in the browser.

What is built in

2 starter examples.

Why this page is useful

The page combines the working tool, starter examples, pre-use checks, and links to the next tools in the same workflow.

Instant results

Regex Tester

Runs in your browserInput type: TextOutput type: Text
Examples
Ready to convert
Input stateInput ready

98 characters · 4 lines

Next actionAuto convert on

Output updates automatically after each change

Output stateWaiting for a valid result

Convert first and the result will be ready here

98 characters · 4 linesPaste input here, adjust it if needed, then convert.
0 characters · 0 linesThe result appears here after a valid conversion.
Your converted output will appear here.

Practical use

When to use Regex Tester

Regex Tester checks whether your Text input is valid, complete and ready to use before you publish it, share it or move it into another workflow. It runs locally in the browser, supports Hebrew and English input, and includes pattern and flags with copy or download actions without uploading data to a server.

  • Pattern and flags
  • Match positions
  • Capture groups

Use cases

Where Regex Tester helps most

  • Test search patterns against real text before moving a regex into code, automation or SEO cleanup work.
  • Review matches, capture groups and positions when debugging a pattern copied from docs, Stack Overflow or another repo.
  • Compare a risky regex against a small sample before running it on production content or logs.

Workflow fit

How to fit the tool into a real workflow

Regex Tester includes 2 starter examples, so it is easier to understand the expected input before doing real work. The page stays focused on the main working direction of the tool.

  • Add pattern= on the first line and optional flags= on the second line.
  • Paste the test text below the key-value lines.
  • Convert to inspect matches, indexes and captured groups.

What you get from the output

How to use the result right after conversion

  • Use the match list to confirm the regex hits only the text you want and not nearby false positives.
  • Inspect capture groups before reusing the pattern in replacements, parsing or validation logic.
  • Promote the regex into code only after the sample text still matches exactly as expected.

Before relying on the result

Quick checks worth doing first

  • Start with the smallest realistic text sample before trusting a complex pattern on long content blocks.
  • Check whether flags, greedy tokens or escaped characters change the pattern meaning more than expected.
  • Avoid running a newly tested regex on production replacements until one manual sample is reviewed.

Starter examples

Examples for Regex Tester

Load one of the examples to start faster, adapt the values to your case, and see how Regex Tester behaves with realistic input.

Each example button inside the tool loads the matching input so you can start without guessing the format.

Email capture

pattern=([\w.+-]+@[\w.-]+\.[A-Za-z]{2,})
flags=g
Support: team@example.com
Sales: hello@demo.co.il

Hebrew order IDs

pattern=#(\d{4})
flags=g
הזמנה #1024 הושלמה
הזמנה #2048 ממתינה

How to use this converter

How to use this converter

  1. Add pattern= on the first line and optional flags= on the second line.
  2. Paste the test text below the key-value lines.
  3. Convert to inspect matches, indexes and captured groups.

FAQ

FAQ

What input does Regex Tester expect?

Regex Tester expects Text input and returns Text output. Start with the sample if you are unsure about the expected structure.

Why did Regex Tester show an error?

Errors usually mean the input is empty, incomplete or not valid Text. Check brackets, quotes, separators and special characters before converting again.

Does this regex tester support flags like g and i?

Yes. Add flags= with values such as g, i, m or combinations like gi to test the same pattern under different matching rules.

When are capture groups useful in regex testing?

They help when you need not only the whole match but also the exact inner parts, such as IDs, emails, domains or numbers that should be extracted later.

Is my data uploaded to a server?

No. The conversion runs in your browser, so your input does not need to leave your device.

Can I use this converter for free?

Yes. The tools are free to use, with simple advertising that helps keep the site available.

Before converting

How to get a cleaner result

  • For developer tools, validate the result before using it in production code or API requests.
  • Try the built-in sample first to understand the expected input shape.
  • Check that the input is complete before copying or downloading the output.
  • If an error appears, reduce the input to a smaller section and test again.

Common issues

What to check if something fails

  • Syntax errors usually come from missing brackets, quotes or separators.
  • Formatted output should still be validated before use.
  • Sensitive code or tokens should not be shared in screenshots.

Next in the workflow

Tools that usually help after this one

These tools are picked for the next practical step so you can keep moving into cleanup, validation, extraction or publishing.

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