Form data prep — flatten objects to single-level for HTML form serialization.CSV export — flatten nested data so it fits a tabular structure.Translation files — convert nested i18n trees to flat dot-keys.Configuration — convert nested config to env-var-style flat keys.

📋

JSON Flattener

Flatten nested JSON into dot-notation keys and unflatten dot-notation back to nested objects. Configurable separator. Free, runs in your browser.

Input JSON

Output JSON

Reference

How does the JSON flattener work?

Flatten converts a nested JSON object like {"a":{"b":1}} into a single-level object with dot-notation keys: {"a.b":1}. Arrays are indexed numerically (a.0, a.1). Unflatten reverses the process. The bracket separator uses a[b][0] notation; slash uses a/b/0.

Common uses

Form data prep — flatten objects to single-level for HTML form serialization.
CSV export — flatten nested data so it fits a tabular structure.
Translation files — convert nested i18n trees to flat dot-keys.
Configuration — convert nested config to env-var-style flat keys.

Privacy

All processing runs 100% in your browser. No data is sent to any server.

← Back to all tools