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Regular Expressions: A Practical Guide for Beginners

Free online regular expressions: a practical guide for beginners. Process data instantly in your browser. No upload, no signup, fully private.

Local processing

Interactive Regex Tutorial

The simplest regex matches literal characters. /cat/ matches the substring "cat" anywhere in the input. Regex is case-sensitive by default; add the i flag to ignore case.

Regex Tester

//

2 matches

I have 42 apples and 7 oranges.
Match details
#MatchIndexGroups
0427—
1721—

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📚 Learn Read "CSV vs TSV: Which Delimiter Format Should You Use?" Compare CSV and TSV across delimiter choice, escaping, compatibility, and use cases — and learn when to pick each for tabular data. 📚 Learn Read "How to Convert Markdown to HTML Step by Step" Step-by-step guide to converting Markdown text to HTML using a free browser-based tool. Learn syntax, extensions, and common use cases. 📚 Learn Read "How to Convert Unix Timestamps to Human-Readable Dates (Step-by-Step)" Step-by-step guide to converting Unix timestamps (epoch) to human-readable dates and back using a free browser-based tool. Learn seconds vs milliseconds. 🔧 Explore Try "CSS Formatter & Beautifier" Free online css formatter & beautifier. Process data instantly in your browser. No upload, no signup, fully private. 🔧 Explore Try "Broken Link Checker" This tool requires external data or server-side processing. Coming soon. 🔧 Explore Try "Age on Other Planets Calculator" Free online age on other planets calculator. Process data instantly in your browser. No upload, no signup, fully private.