RegExpress

Build, test, explain, and optimize regex with five engines, a focused editor, visual tools, test suites, code generation, and a generous free tier.

RegExpress is a complete regular expression toolkit for iPhone, iPad, and Mac. Create, test, understand, and refine regex patterns in one focused workspace, whether you are learning the basics or maintaining production expressions.

Test with the flavor you actually use. RegExpress supports Swift Regex, Foundation (ICU), JavaScript/ECMAScript, Python Compatibility Mode, and native PCRE2. Flavor-aware options, syntax references, examples, diagrams, comparisons, and compatibility details help you spot differences before they become bugs.

Write and test with confidence

See live matches and capture groups as you type. Switch between automatic and manual execution, inspect clear errors, and keep the editor responsive during demanding patterns. Built-in safety analysis identifies potential backtracking risks, while find and replace lets you preview changes before applying them.

Focus on complex patterns

Open the multiline Focus Editor for more room, syntax-aware tools, a persistent token dock, flavor-specific options, visual railroad diagrams, code snippets, and quick access to the Pattern Builder, test suites, and reference material.

Understand and improve every expression

Turn plain-language requirements and examples into a regex. Explore explanations, recommendations, optimization suggestions, debugging tools, diagrams, and a searchable cheat sheet. Compare patterns by matches, compatibility, and performance to choose the right approach.

Build a reusable regex workflow

Save patterns, organize them into folders and automatic collections, keep history, and create test suites with positive and negative cases. Save complete .regexpress workspaces, reopen .regproj test projects, import shared content, and generate code for your project. A command palette, Spotlight integration, App Shortcuts, multiwindow support, and sharing tools keep common actions close at hand.

Learn by doing

Browse flavor-aware examples, follow guided tutorials, use the syntax reference, and practice with challenges designed for different skill levels.

A useful free experience

Core editing, unlimited live matching, all five engines, standard options, capture results, find and replace, examples, reference material, and Swift code generation are free. You can also save up to 20 patterns, keep 50 recent history items, create one test suite with up to 10 manual cases, and use selected previews of advanced tools.

RegExpress Pro is available as a one-time purchase with no subscription. Pro unlocks deeper debugging and performance analysis, complete visual tools, advanced generation and optimization, additional code targets, unlimited tests and saved content, iCloud sync, advanced organization, and more.

Whether you need a quick match, a visual explanation, or a repeatable testing workflow, RegExpress helps you build regex with clarity and confidence.