Frequently Asked Questions
How can I test a YARA rule online for free?
Paste or write your rule in the Rule Editor, add a sample and click Run – everything executes locally in your browser.
Does YARA Playground run completely in my browser?
Yes. The validator uses WebAssembly to compile the official libyara engine locally, so your samples never leave your device.
What is the maximum file size I can upload?
You can upload text or binary samples up to 10 MiB per scan.
Is YARA Playground Online using the official YARA engine?
Absolutely. We compile the upstream libyara via Emscripten to WebAssembly, ensuring results match the CLI.
Is YARA Playground Online really free?
Yes – it's free to use. If you find it useful you can buy me a coffee to support development.
What is YARA?
YARA is an open-source pattern matching engine widely used in malware research. It lets you define rules with text, hex or regex-like strings and logical conditions to identify files.
How does YARA differ from regular expressions?
Regular expressions operate on plain text; YARA can match binary data, use wildcards, count occurrences, reference PE headers and combine conditions, making it far more powerful for security work.