Small tools for real JSON problems
Map a payload, recover a broken sample, reconcile two result lists, or generate TypeScript. These tools run in your browser with no account, upload, or installation.
JSON to diagram
Explore nested structure, hide values, and export a diagram as SVG or Mermaid.
Generate a diagram → 02 · Recover usable JSONJSON repair with a report
Repair copied logs, Python-style values, and almost-JSON. Review what changed before exporting.
Repair JSON → 03 · Reconcile two listsJSON array diff by ID
Match records by id or sku and find actual changes, even when an API returns a different order.
Compare records → 04 · Generate typesJSON to TypeScript
Infer nested interfaces, optional properties, and nullable unions from real JSON samples.
Generate TypeScript →Take the next step with the same data
Start with repair if your copied sample will not parse. Use a diagram to explain its structure, array diff to compare two snapshots, and TypeScript generation to bring a representative sample into your project. Each tool includes an example and explains its limits.
Inputs are not saved in website storage or sent to Analytics. Copy and download are explicit actions. Read the data-handling details before sharing exported results.
Need these tools while viewing an API response?
The CodePrettify extension and Windows app put JSON inspection, transformation, diagrams, and code generation beside your documents.