# FlatNest

> Flatten and unflatten JSON in your browser.

- Website: https://flatnest.surge.sh
- AZN8 listing: https://azn8.com/listing/flatnest
- Pricing: Free forever; Pro early-bird by email · Freemium
- Categories: [Developer tools](https://azn8.com/category/developer-tools), [Productivity](https://azn8.com/category/productivity)
- Listed: 2026-10-05
- Updated: 2026-10-05
- JSON: https://azn8.com/api/v1/listings/flatnest

## About

Free online JSON flattener & unflattener. Paste nested JSON, get dot-notation keys (or reverse). 100% in-browser — no upload, no signup. Handy for CSV export, Elasticsearch mappings and config diffs.

## Features

- Flatten nested JSON to dot keys
- Unflatten flat keys back to nested JSON
- Runs fully in-browser
- No signup required

[Try free](https://flatnest.surge.sh)