Dev & data tools

Format JSON, generate IDs, and prep test data — all in your browser.

JSON formatter UUID generator Subnet / CIDR Random CSV Token generator
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Quick guide

  1. Format and validate JSON before sharing.
  2. Generate test data (CSV + schema) and reuse it via shareable URLs.
  3. Compute subnets, usable ranges, and capacity from an IP and prefix.

Tools

Calculators