JSON Flatten

ReadyHow to use

Flatten nested JSON to dot-notation keys, or unflatten back.

TransformationObject & schemaBrowser workspace

Free to use. No account, no daily limit, and no backend processing for tool input.

Tip: use samples, upload, copy, download, and send-to actions inside the workspace where available.

What is JSON Flatten?

JSON Flatten Converter is a free, browser-based tool that helps you convert between formats. Flatten nested JSON to dot-notation keys, or unflatten back. It's built for speed and privacy: Everything runs locally in your browser — your data is never uploaded to a server. No sign-up, no installs, and no daily limits.

How to use JSON Flatten

1Paste your JSON into the input panel, or drag-and-drop a file (you can also load a built-in sample).
2Adjust the conversion options — delimiter, formatting, and field handling — to match your data.
3Review the result in the output panel and copy it or download it as a file.

Features

Auto-detects delimiters and structure
Round-trips cleanly between formats
100% client-side — no upload, fully private
Free with no account, no watermark, and no daily limit
Works on large inputs, limited only by your device's memory
Load a sample, then copy, download, or share your result

Common uses

Migrating data between APIs, databases, and spreadsheets
Quick one-off converter jobs without opening a heavy app
Preparing data before importing it elsewhere
Sharing a reproducible result with a teammate via a link

Used by

Data engineers
Backend developers
API developers
Data analysts
Data migration teams
Integration engineers

Common errors

Headers or keys are not consistent across records.
Delimiter, quote, or encoding settings do not match the source file.
Nested fields need flattening before the result works as a table.
Blank values are mistaken for zeros or real values instead of remaining explicit.

How it works

1Reads the JSON input in the browser.
2Maps fields into the target structure.
3Renders a preview and exportable output.

Recommended workflow

1
Prepare the input
Start with the source file or pasted payload, then confirm delimiters, headers, and field handling before conversion.
2
Run JSON Flatten
Review the preview, copy or download the result, and keep everything local in your browser.
3
Next recommended tool
JSON Formatter: Pretty-print, minify, and indent JSON safely.
Open tool
4
Then continue with
JSON Merge: Deep-merge two or more JSON documents with conflict policy.
Open tool
5
Then continue with
JSON Compare: Side-by-side diff of two JSON documents with structural alignment.
Open tool

Frequently asked questions

How do I use JSON Flatten?: Paste or drop your data into the workspace, adjust the options to fit your data, then copy or download the result. Flatten nested JSON to dot-notation keys, or unflatten back.
Is my data uploaded or stored anywhere?: No. Everything runs locally in your browser — your data is never uploaded to a server. Nothing is sent to a server, so it's safe to use with private or sensitive data.
Is JSON Flatten Converter free?: Yes — it's completely free with no account, no sign-up, no watermark, and no daily usage limits.
What's the maximum file size?: There's no hard limit imposed by the tool. Because processing happens in your browser, the practical ceiling is your device's available memory — most everyday files work instantly.
Do I need to install anything?: No installs and no extensions — it runs entirely in your web browser and even works offline once the page has loaded.

JSON Flatten

ReadyHow to use

Flatten nested JSON to dot-notation keys, or unflatten back.

TransformationObject & schemaBrowser workspace

Free to use. No account, no daily limit, and no backend processing for tool input.

Direction

Separator

Arrays

Empty

Input JSONJSON

Try a sample:

Tip: use samples, upload, copy, download, and send-to actions inside the workspace where available.

What is JSON Flatten?

How to use JSON Flatten

1Paste your JSON into the input panel, or drag-and-drop a file (you can also load a built-in sample).
2Adjust the conversion options — delimiter, formatting, and field handling — to match your data.
3Review the result in the output panel and copy it or download it as a file.

Features

Auto-detects delimiters and structure
Round-trips cleanly between formats
100% client-side — no upload, fully private
Free with no account, no watermark, and no daily limit
Works on large inputs, limited only by your device's memory
Load a sample, then copy, download, or share your result

Common uses

Migrating data between APIs, databases, and spreadsheets
Quick one-off converter jobs without opening a heavy app
Preparing data before importing it elsewhere
Sharing a reproducible result with a teammate via a link

Used by

Data engineers
Backend developers
API developers
Data analysts
Data migration teams
Integration engineers

Common errors

Headers or keys are not consistent across records.
Delimiter, quote, or encoding settings do not match the source file.
Nested fields need flattening before the result works as a table.
Blank values are mistaken for zeros or real values instead of remaining explicit.

How it works

1Reads the JSON input in the browser.
2Maps fields into the target structure.
3Renders a preview and exportable output.

Recommended workflow

1
Prepare the input
Start with the source file or pasted payload, then confirm delimiters, headers, and field handling before conversion.
2
Run JSON Flatten
Review the preview, copy or download the result, and keep everything local in your browser.
3
Next recommended tool
JSON Formatter: Pretty-print, minify, and indent JSON safely.
Open tool
4
Then continue with
JSON Merge: Deep-merge two or more JSON documents with conflict policy.
Open tool
5
Then continue with
JSON Compare: Side-by-side diff of two JSON documents with structural alignment.
Open tool

Frequently asked questions

How do I use JSON Flatten?: Paste or drop your data into the workspace, adjust the options to fit your data, then copy or download the result. Flatten nested JSON to dot-notation keys, or unflatten back.
Is my data uploaded or stored anywhere?: No. Everything runs locally in your browser — your data is never uploaded to a server. Nothing is sent to a server, so it's safe to use with private or sensitive data.
Is JSON Flatten Converter free?: Yes — it's completely free with no account, no sign-up, no watermark, and no daily usage limits.
What's the maximum file size?: There's no hard limit imposed by the tool. Because processing happens in your browser, the practical ceiling is your device's available memory — most everyday files work instantly.
Do I need to install anything?: No installs and no extensions — it runs entirely in your web browser and even works offline once the page has loaded.

What is JSON Flatten?

How to use JSON Flatten

Features

Common uses

Used by

Common errors

How it works

Recommended workflow

Prepare the input

Run JSON Flatten

Next recommended tool

Then continue with

Then continue with

Frequently asked questions

What is JSON Flatten?

How to use JSON Flatten

Features

Common uses

Used by

Common errors

How it works

Recommended workflow

Prepare the input

Run JSON Flatten

Next recommended tool

Then continue with

Then continue with

Frequently asked questions