JSON Schema Migration Assistant
Compare flat object schemas, map renamed fields and check sample records against a declared target contract.
Flat object subset: required, additionalProperties, scalar type/enum, numeric bounds and string length. Optional defaults and explicit aliases only. References, patterns, nested validation and combinators are not evaluated; unsupported keywords are disclosed.
Using JSON Schema Migration Assistant
Compare flat object schemas, map renamed fields and check sample records against a declared target contract.
- Open supported files in their intended order, or try the ready worked example. Binary formats use exact local files; tabular formats use a header row or JSON objects.
- Open Details & settings to choose explicit fields, rules or methods. Select a record to inspect its source evidence and add review notes. Import-repair replacements require individual approval.
- Use Preview for result tables, metrics, charts and method assumptions. Review missingness, warnings and unsupported features before relying on a result.
- Download the workflow ZIP for data, task-specific artifacts, settings and source fingerprints. Save review to reopen your decisions with the exact original files.
Example
Try the worked example for a complete source/configuration/result workflow. It includes task-specific edge cases such as invalid cells, conflicting duplicates, malformed rows, ambiguous numbers or unresolved references. Review the findings and preview before exporting.
Questions & answers
What does JSON Schema Migration Assistant support?
Flat object subset: required, additionalProperties, scalar type/enum, numeric bounds and string length. Optional defaults and explicit aliases only. References, patterns, nested validation and combinators are not evaluated; unsupported keywords are disclosed.
What is in the downloads?
The primary ZIP includes result CSV/JSON, findings, source fingerprints, settings and task-specific artifacts described by the tool. Analysis workflows also include chart SVGs when applicable. CSV formula escaping is on by default; JSON preserves types and exact tagged binary values. Original sources can be downloaded separately.
Can I reopen my work and are files sent to a server?
Processing runs locally in this browser with local libraries and bounded workers. Save review retains settings, decisions and exact source fingerprints; reopen it with the matching original files. Sources are not automatically uploaded or fetched from URLs. Public pages retain the site’s approved ads and optional analytics.
What are the practical limits and review requirements?
Up to eight files and 80 MiB total, normally 25 MiB per file. The line slicer accepts an 80 MiB source and exports up to 25 MiB. Data workflows support 50,000 rows and 300 columns; binary parsers have depth/object guards and analysis simulations have explicit work budgets and a 30-second timeout. Review source evidence, assumptions and the result in your target application; unsupported features are not silently treated as supported.
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