Browser-native developer utilities
Dev-Tools for messy engineering work.
Inspect, generate, encode, decode, and convert without uploading anything anywhere.
RFC3339 / DateTime Playground
Validate an instant and see exactly how common runtimes interpret it.
Try Z, an explicit offset, or more than 3 fractional digits.
How to use this tool
Paste a timestamp. The strict RFC3339 check requires a date, time, seconds, and either Z or a numeric offset. JavaScript keeps only millisecond precision; the normalized UTC display preserves your original fractional precision.
CORS Debugger
Model a browser request and diagnose the response headers.
How to use this tool
Enter the page origin, API URL, request method and relevant request/response headers. This simulates the browser’s CORS checks; it does not send a network request. A failed HTTP status is different from CORS: the server replied, but CORS may prevent JavaScript from reading it.
HTTP/API Error Inspector
Turn a raw response into a practical client-side action.
How to use this tool
Paste a status line, headers, and optional body. The inspector recognizes Problem Details JSON, authentication failures, rate limiting, server failures, and retry hints. Its retry recommendation is a safe default, not knowledge of whether your operation is idempotent.
Retry / Backoff Calculator
See the delays, jitter range, and total wait before shipping a retry policy.
How to use this tool
Choose the number of retries after the first failed request. Full jitter picks any delay from zero to the calculated cap and helps prevent synchronized retry storms. The total shown is the maximum configured wait, excluding request duration.
Service Bus Message Size Calculator
Estimate payload pressure before a message reaches the broker.
How to use this tool
Paste the exact message body and choose the applicable broker limit. UTF-8 size is exact; AMQP envelope size is an estimate you can tune. Base64 is calculated exactly. Gzip is measured locally when the browser supports CompressionStream. Always leave room for application properties.
JSON Workbench
Shape, inspect, convert, and measure JSON in one place.
How to use this tool
Paste a JSON value, then choose an operation. Size and validity update immediately. Generated C# and TypeScript are intentionally lightweight starting points: review nullability, names, unions, and numeric types before production use.
JWT Inspector
Decode claims and spot lifecycle problems without sharing a token.
Decoding is not signature verification. Never trust a token based on this view alone.
How to use this tool
Paste a three-part JSON Web Token. Header and payload are Base64URL-decoded locally. Expiration, issue time, issuer, audience, scopes, and roles are summarized. This tool does not fetch keys or verify the signature.
Connection String Inspector
Understand configuration while keeping secrets out of the result.
How to use this tool
Paste a SQL Server, PostgreSQL URI, Azure Storage, Service Bus, or Redis connection string. Recognized secret fields are always redacted in the structured output. Treat the original input as sensitive even though it never leaves this browser.
Cron Expression Visualizer
Read a schedule and preview its next local executions.
Preview times use your browser timezone:
How to use this tool
Enter a standard five-field Linux expression using numbers, *, lists, ranges, and steps. The preview supports Linux cron. Azure Functions adds a leading seconds field; Quartz uses seconds and a distinct day-of-week/day-of-month model, so those dialects are explained but not silently reinterpreted.