RegExp vs Regex Tester Pattern Editor

RegExp is a regular expression tester for developers, on Mac, iPhone and iPad. Write a pattern, paste your text, and see every match and capture group as you type, with the same engine your code uses. Six flavors, real engines: • Swift Regex • NSRegularExpression (Objective-C and Swift) • JavaScript (ECMAScript) • PCRE2, the engine of PHP • Go and Go (POSIX) Write and understand patterns: • Matches and capture groups highlighted in the test string, with their names • Errors marked right in the pattern, unbalanced brackets too • Substitution with each engine's replacement syntax, and a list mode that extracts one line per match • A quick reference of each flavor's syntax: select an item to insert it • Copy the pattern as ready-to-use Swift, Objective-C, JavaScript, Go or PHP code • Jump between matches; slow patterns time out instead of freezing the app Keep your patterns: • Sessions and folders, your own regex notebook, synced with iCloud across your devices • Search, duplicate, export and import sessions, or open one in its own window • Shortcuts actions, Spotlight search, and a Services menu item on the Mac for selected text Most of RegExp is free. RegExp Pro, a one-time purchase that works with Family Sharing, adds: • Explain: what every part of a pattern does, in plain language, and what the selected flavor doesn't support • Test cases: strings a pattern must or must not match, checked on every run • Apple Intelligence: write a pattern from a description, or get a summary of one (on supported devices) • The advanced options of every flavor RegExp speaks English, German, French, Spanish, Italian, Portuguese, Ukrainian, Russian, Japanese and Chinese. Made by an independent developer. Questions or ideas? Write to support@loshadki.app.

Test a regular expression on your iPhone and see every match light up the moment you type it. Paste your text, write your pattern, and watch matches highlight character by character — no desktop, no compile step, no guessing. Most regex help on a phone is a static article you read. Regex Tester is a working engine: it runs your pattern with Foundation's NSRegularExpression (the same ICU syntax iOS itself uses), so what you see here is exactly what your app, script, or config will do. Invalid pattern? You get a plain-English reason instead of a cryptic engine dump. WHAT YOU GET - See every match highlighted inside your own test text, updating live as you type - Know exactly what each capture group grabbed — numbered and named, with character ranges - Preview a find-and-replace before you commit it, using $1 / $2 templates on your real text - Flip case-insensitive, multiline, dot-all and ignore-whitespace modes with one tap and watch results change - Start from 19 ready-made patterns for email, URL, IPv4, phone, hex color, ISO date, UUID, JWT and more — searchable and filtered by Validation, Extraction, Web and Format - Look up any token without leaving the app: character classes, anchors, quantifiers, groups, lookaround and replacement templates in a built-in cheatsheet - Bookmark the patterns you keep reusing with their test text and flags, and reload any of them in one tap PERFECT FOR - Developers who need to sanity-check a pattern away from their machine - Data and log wranglers pulling IDs, dates or fields out of messy text - Students and self-taught coders learning regex by seeing it behave, not by reading about it - Anyone writing validation rules for forms, imports or search filters WHY NOT JUST USE A WEBSITE? Online regex testers need a connection, and they want you to paste your text into someone else's server — a hard no when that text is a customer export, a log dump, or anything under NDA. This runs entirely on-device, works on a plane or in a basement, and keeps a keyboard-friendly phone layout instead of a desktop page squeezed onto a small screen. PRIVACY Every pattern, test string and result is processed on your device and stored on your device. No account, no ads, no tracking, no upload — there is no server to send anything to. FULL ACCESS Live matching, the pattern library and the basics of the syntax reference are free to use. Full Access unlocks capture-group inspection with ranges, the live replace-with-template preview, the complete cheatsheet (quantifiers, groups, lookaround, replacement templates and engine notes), and saved patterns. Choose the plan that fits: weekly, yearly, or a one-time lifetime unlock that never renews. Open the Test tab, paste the text that is giving you trouble, and write the pattern that fixes it. Terms of Use (EULA): https://web-levi.web.app/terms Privacy Policy: https://web-levi.web.app/privacy-policy Questions? tphuc.work@gmail.com