What it does: The Regex Tester lets you enter a regular expression and sample text, instantly showing matches directly in your browser.
Key features: • Text‑input – type your pattern and test string. • Live preview – matches are highlighted as you type. • Copy – one‑click copy of the matched results for easy reuse.
Why use it? The Regex Tester provides a fast, no‑install solution for developers, QA engineers, and anyone working with pattern matching. It eliminates the need for external IDE plugins and works on any device with a modern browser.
Basic usage steps: 1. Paste or type your regex in the “Pattern” field. 2. Enter the text you want to test in the “Test String” area. 3. The preview updates automatically, highlighting every match. 4. Click the copy icon to copy the highlighted results to the clipboard. 5. Adjust flags (g, i, m, s, u, y) using the optional flag selector if needed.
Short example: Pattern: \b\d{3}-\d{2}-\d{4}\b Test string: “My SSN is 123-45-6789 and my phone is 555‑1234.” The preview will underline “123-45-6789”, showing the regex correctly captures a US‑style SSN.
Tips for debugging: • Test with simple patterns first, then add complexity. • Use the ^ and $ anchors to ensure full‑string matches. • Turn on the global flag (g) to see all occurrences.
Essential notes: • Use proper delimiters and flags; for case‑insensitive matching add the i flag. • All processing happens locally; no data leaves your device, ensuring privacy. • Very large inputs may slow the live preview – consider testing with smaller snippets first. • The tool supports JavaScript‑compatible regex syntax only.
Ready to streamline your regex workflow? Try the Regex Tester now
FAQ
Can I test multi‑line patterns?
Yes. Enable the m (multiline) flag to allow ^ and $ to match the start and end of each line within your test string.
Does the tool support regex flags?
All standard JavaScript regex flags (g, i, m, s, u, y) are available via the flag selector for precise control.
Is my data saved on the server?
No. All processing occurs in the browser; your patterns and test strings never leave your device.
What size of text can I test?
The tool handles typical code snippets and paragraphs comfortably. Extremely large files may affect performance, so test large data in smaller chunks.