How do I use this regex tester?
Enter a regular expression, paste the text you want to test, choose flags, then run the match to see highlighted results and capture groups.
Regex Tester Online.
Use this free online regex tester to test regular expressions, debug matches, inspect capture groups, and check Google Analytics regex patterns. All processing executes immediately in your browser sandbox. 100% private, offline-first.
Free online regex tester
Test regular expressions in your browser
Use this Regex tester to write a pattern, test it against sample text, and instantly see every match highlighted. The tool helps you debug regular expressions with global, case-insensitive, and multiline flags before using them in code, forms, analytics reports, or validation rules.
This online regex tester is useful for checking email patterns, URL matching, log parsing, search filters, and capture groups. Because the regex tester runs online in your browser, your test strings stay local while you refine the expression.
If you need a Google Analytics regex tester, paste example page paths, campaign names, search terms, or event labels into the test area and verify whether your pattern matches the traffic segment you expect before applying it in Google Analytics.
How to use the regex tester
- 1. Enter your regex pattern in the Regex field.
- 2. Paste the text, URL list, or analytics sample data you want to test.
- 3. Select the global, insensitive, or multiline flags you need.
- 4. Click Run Match to view highlighted matches and capture groups.
Regex tester FAQ
Is this online regex tester free?
Yes. This online regex tester is free and runs directly in your browser without uploading your text to a server.
Can I test Google Analytics regex?
Yes. Use it to test Google Analytics regex patterns against example URLs, campaign names, page paths, or event strings.
Related tools
More text & data tools to try next
Explore more browser-based text and data utilities for formatting, encoding, comparing, counting, and cleaning content before it reaches production.
JSON Formatter & ValidatorFormat, validate, beautify, and minify raw JSON strings with clear error feedback.XML FormatterClean up, indent, and validate XML documents for APIs, feeds, and configuration files.Online Word CounterCount words, characters, sentences, paragraphs, reading time, and word density with a free online word counter.Case ConverterConvert text to title case, sentence case, upper case, lower case, capital case, camelCase, snake_case, and more.Base64 Encoder & DecoderEncode text to Base64, decode Base64 strings, and convert Base64 to text with a free online Base64 converter.URL Encoder & DecoderEncode URLs, decode URL strings, process URI components, and copy clean encoded links with a free online URL encoder decoder.
More FAQ
More questions about using this tool
When should I use Regex Tester Online?
Use Regex Tester Online when you need a focused browser utility for a quick text & data tools task without opening heavier software or setting up a separate workflow.
Should I review the output before using it?
Yes. Always check the generated, converted, formatted, or calculated result before sharing it, saving it, or using it in production work.
Can I use this tool for sensitive work?
For sensitive files or text, prefer tools that process locally in the browser and avoid pasting secrets, private credentials, legal documents, or financial data into any tool unless you understand how it handles data.
What should I do if the result looks wrong?
Check the input format, remove unsupported characters or damaged file content, try a smaller sample, and compare the result with the original before continuing.
Are online tools good for repeated daily tasks?
Yes. Browser tools are best for small repeatable jobs such as formatting, converting, compressing, comparing, generating, previewing, and calculating without installing extra apps.
regex-tester.island
Idle
Regex:
//
Flags:
TEST STRING
MATCH RESULTS & PREVIEW0 matches
Capture Groups details will print here.
Invalid input data format.