Frequently Asked Questions
Master Regular Expressions in Real-Time
Common Questions & Platform Details
Direct answers from the RegExLab engineering team regarding syntax engines, cross-browser performance, data handling, and workspace exports.
How does RegExLab handle PCRE vs. ECMAScript syntax differences?
RegExLab defaults to the ECMAScript 2023 standard for client-side validation, but our backend compiler supports PCRE2 lookbehind assertions and atomic grouping. Toggle the engine selector in the top-right toolbar to switch between `ECMAScript`, `Python (re)`, and `Go (regexp)` modes. Each mode highlights unsupported tokens in amber and suggests equivalent patterns using native language functions.
What browsers and environments are fully supported?
The playground runs natively on Chrome 118+, Firefox 120+, Safari 16.4+, and Edge 118+. We leverage a WebAssembly-compiled `re2` engine for consistent performance across all supported browsers. Server-side execution via our CLI tool (`regexlab-cli v3.2.1`) requires Node.js 18.x or Deno 1.38+ and mirrors the web interface exactly.
Is my test data or regex pattern stored on your servers?
No. RegExLab operates strictly on a client-side architecture. All pattern compilation, matching, and backtracking visualization happen directly in your browser's memory. We do not log, cache, or transmit your input strings, test cases, or workspace configurations. Optional cloud sync uses end-to-end AES-256 encryption and requires explicit OAuth 2.0 authorization.
Which export formats are available for my workspaces?
You can export validated patterns and test datasets as JSON, YAML, or CSV via the `File > Export` menu. For developer integration, we support generating ready-to-use code snippets in JavaScript, Python, Rust, and C#. The JSON export includes metadata like compile time, capture group mappings, and performance benchmarks measured in nanoseconds per match.
Still Need Assistance?
Our documentation covers advanced backtracking analysis, custom flag configurations, and CI/CD pipeline integration. Ready to test your patterns?