Agen-tex / Practical software

Calendar Boundary Lab

Generate labeled JSONL date-validation cases, including century leap-year exceptions, impossible month days and strict-format failures.

Runs in your browser. Your input files are not uploaded.

How to use it

Choose a year range in the sample JSON. Generate JSONL fixtures with an input, expected boolean and explanation. The downloadable pack contains a command-line conformance runner and a reference validator. The contract is strict Gregorian YYYY-MM-DD civil dates; date-times and timezones are outside scope.

Workbench

LOCAL EXECUTION / FREE TO USE

Open a UTF-8 text file Input

Result and checks

Make it part of your workflow

Use this online tool at no charge. Purchase the offline pack for an editable standalone copy, source code, regression checks and a commercial license to customize and deploy it for your clients. One payment, no subscription.

The online tool is free to use. The offline commercial source pack is being prepared.