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Nablyx

Compare JSON files online free

Nothing uploadedTested up to 50 MB

Compare two JSON documents structurally and review added, removed, changed, and type-changed values by path. Object key order never counts as a change.

Compare two JSON files structurally to see added or removed keys and changed or type-changed values at their exact paths. Nested objects are traversed, object-key order is ignored, and arrays can be matched by index or by an identity field; ambiguous identity matches are reported with a warning. Both files are processed in your browser and never uploaded, up to 50 MB each. The configured cap is based on repeated fresh-browser tests of the hardest deeply nested input shape: that shape stayed within the measured ceiling at the cap, while the next larger worst-case rung exceeded the 2 GiB safety ceiling. For files near the cap, expect a memory-intensive comparison and close other memory-heavy tabs or apps first.

Processed locally in your browser

JSON comparison workspace

Choose two JSON documents, then decide how array elements should be paired.

Array matching

Element 0 is compared with element 0. Trailing elements are added or removed.

Diff findings will appear here

Choose two valid JSON documents and run the structural comparison.

Find meaningful JSON changes

  1. 1

    Choose the earlier and later JSON documents.

  2. 2

    Match arrays by index or select an identity field such as id.

  3. 3

    Run the comparison locally in your browser.

  4. 4

    Review exact totals and path-level findings.

  5. 5

    Download the findings-only JSON report.

Built for the real task

  • Object key order ignored
  • Array matching by identity or index
  • Type changes reported separately
  • Findings report only — no merge or patch

See the transformation

Two documents become a path-by-path findings ledger.

See where values or data types changed without being distracted by harmless key-order differences.

A.json
{"id":42,"price":49,"active":true}
B.json
{"active":"true","price":44,"id":42}
Result
items[id=42].price49 → 44
items[id=42].activeboolean → string

Browser limits

Files are limited to 50 MB to protect browser stability, especially on phones. Processing stays on this device.

Object key order ignored

Compare two JSON documents structurally and review added, removed, changed, and type-changed values by path. Object key order never counts as a change.

Private by design

The selected file is not uploaded to Nablyx.

Processed locally in your browser

No. This tool reads and transforms the file locally in your browser.

Common uses

  • Object key order ignored
  • Array matching by identity or index
  • Type changes reported separately
  • Findings report only — no merge or patch

Does this tool merge or modify either JSON document?

No. It reads both documents locally and produces a findings report. It never creates a merged or patched document.

Related guide

How to Compare Two JSON Files (and Find What Really Changed)

Related tools

Continue with a related Nablyx tool.

Ready to work on your file?

Return to the workspace and process it locally.

Compare JSON documents