Regex Tester

Test regular expressions in your browser. No uploads, no tracking — everything runs locally.

Input text

Result

Matches: 2•Flags: gm

Hello world! Email: test@example.com Phone: +1 (555) 123-4567 Order IDs: A-10293, A-10294 Dates: 2026-01-05, 05/01/2026
Matches list
  • A-10293#1 @ 73
  • A-10294#2 @ 82
Tip: Common shortcuts — \\d (digit), \\w (word char), . (any char), groups ( ), and alternatives a|b.

What is a Regex Tester?

A regex tester is a tool that helps developers build, test and debug regular expressions against sample text. Regular expressions (regex for short) are pattern-matching rules used to extract, validate or transform strings. They are commonly used in backend validation, log parsing, scraping, data extraction, security filtering and search engines.

Why developers use regex

  • Extracting data from logs or HTML
  • Validating emails, URLs and user input
  • Searching and replacing patterns in text
  • Cleaning up or transforming data during ETL processes
  • Parsing API payloads or configuration files

How to use this Regex Tester

  1. Enter a regex pattern in the pattern input field
  2. Enable flags such as g (global), m (multiline) or i (ignore case)
  3. Paste text into the sample input area
  4. The tool highlights all matches and shows a match list below
  5. Optionally switch to Replace mode to substitute matches

Regex flags and what they mean

gGlobal — find all matches, not just the first one
mMultiline — makes ^ and $ work per line
iIgnore case — makes matching case-insensitive

Common regex patterns

  • Email: [A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}
  • IPv4: ((25[0-5]|2[0-4]\d|[0-1]?\d\d?)\.){3}(25[0-5]|2[0-4]\d|[0-1]?\d\d?)
  • Hex color: #([A-Fa-f0-9]{3}|[A-Fa-f0-9]{6})
  • Phone: \+?[0-9\-$begin:math:text$$end:math:text$\s]{7,15}
  • UUID: [0-9a-fA-F]8-[0-9a-fA-F]4-[1-5][0-9a-fA-F]3-[89abAB][0-9a-fA-F]3-[0-9a-fA-F]12

Example input

Emails:
admin@example.com
test.user+1@gmail.com

Order IDs:
A-1023
B-5542

Example matches

With pattern: [A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+ and flag g, the tool correctly extracts both email addresses from the text.

Is my data safe?

This Regex Tester runs 100% client-side in your browser. No data is uploaded or transmitted to any server or third-party endpoint, making it safe for use with logs, tokens or temporary debug text.

Related tools

  • Base64 — encode/decode regex matches
  • JSON Formatter — clean up JSON from logs and responses
  • JWT Decoder — inspect authorization tokens containing JSON
  • Cron Builder — build scheduler expressions for backend tasks

Regular expressions remain an essential part of modern development workflows, and a dedicated tester saves time when debugging, validating and constructing patterns.