How to open .JSON files (JSON data) on Android, Windows and Linux

JSON files come out of everything: an app’s export, a “download your data” archive, a game’s save folder, a settings file, the network log a support team asked you for. Open one in the wrong place and you get a single line of brackets and quotes thousands of characters long, or a phone that says it has no app for it.

Folders opens JSON in its text editor on Android, Windows and Linux. Keys, strings and numbers are coloured, and Format JSON turns that one long line into neatly indented text you can actually read.

What is a .json file?

JSON (JavaScript Object Notation) is a plain-text format for structured data. It has only a few building blocks: objects in curly brackets ({ "name": "Ada", "age": 36 }), lists in square brackets ([1, 2, 3]), strings in double quotes, numbers, true, false and null. It grew out of JavaScript, was popularised by Douglas Crockford in the early 2000s, and is now a published standard that almost every programming language reads and writes.

Plain JSON is strict. Keys and strings need double quotes, comments aren’t allowed, and there must be no comma after the last item in a list. Those rules are exactly why the variants below exist:

Extension	What it is	Where you meet it
.json	Standard JSON data	App and website exports, settings, APIs, data archives from social networks
.geojson	JSON that describes places: points, lines and areas, each with properties	Maps, open-data portals, GIS work, route exports
.jsonc	JSON with // and /* */ comments	Editor and project settings (VS Code’s settings use it even when the file is named settings.json)
.json5	A relaxed JSON: comments, single quotes, unquoted keys, trailing commas	Config files for some JavaScript tools
.har	HTTP Archive: a browser’s record of every request a page made	Exported from the developer tools in Chrome, Edge or Firefox, usually because support asked

One GeoJSON detail catches everyone once: coordinates are written longitude first, then latitude, the opposite of how most map apps show them.

How to open a .json file with Folders

On Android:

1. Install Folders from the download page and give it access to your files.
2. Find the file, or type its name into search. Data exports often come zipped: tap the ZIP in Folders and then the .json inside.
3. Tap the file to open it in the text editor.
4. If an app sent it to you, tap it there and choose Open with → Folders.

On Windows and Linux:

1. Browse to the file in Folders and double-click it.
2. On Windows, you can also right-click it in File Explorer and choose Open with → Folders; the installer adds Folders to that menu for JSON files.

What you can do with it in Folders

• Format JSON re-indents the whole file with two spaces per level. If the file isn’t valid JSON, Folders says “Invalid JSON” with the reason and leaves the text alone, which makes it a quick validity check.
• Colours for keys, strings, numbers and true/false/null in .json, .geojson and .har files. JSONC and JSON5 files show their comments in a colour of their own.
• Find, Find and replace (with Match case) and Go to line, for when an app reports “unexpected token at line 212”.
• Edit and Save, with undo and redo. Document info shows the line, column, encoding and line endings.
• Big files open at once. HAR files and data exports often run to many megabytes. Folders shows a large file in a read-only view straight away, where Find and Go to line still work; Edit loads it into the editor (up to 8 MB), and then Format JSON works too. Colours are left out for very large text, to keep typing smooth.

Two special cases: Lottie animations are often saved as .json, and Folders plays them instead of showing text (to see the code, right-click the file on a computer, or long-press it on a phone and choose All actions…, then Open with… → Text editor; more in how to open Lottie files). Jupyter notebooks (.ipynb) open as their JSON text, not as a notebook.

Format JSON follows strict JSON. A JSONC or JSON5 file with comments or trailing commas is reported as invalid (formatting would also drop the comments), but it still opens, edits and saves normally. GeoJSON shows as text, not as a map.

Other ways to open .json files

• Firefox has a built-in JSON viewer with a collapsible tree, a raw view and a pretty-print button.
• VS Code or Notepad++ for editing, and jq on the command line for picking data out of big files.
• geojson.io or QGIS draw GeoJSON on a map.
• Chrome’s developer tools can import a .har file into the Network panel to replay the request list.

Problems opening a .json file?

• Everything is on one line. That’s normal for machine-written JSON. Press Format JSON.
• “Invalid JSON”. Look for a comma after the last item, single quotes, comments, or a file that ends abruptly because a download was cut off. The reason Folders shows usually points at the spot.
• It plays an animation instead of showing text. It’s a Lottie file. Use Open with… → Text editor.
• Accented letters show as \u00c3\u00a9. The \u codes are JSON’s normal escapes, but some data exports, Facebook’s among them, are known to write each byte of a UTF-8 letter as its own escape. The data is there; a short script can repair it.

Questions people ask

How do I open a JSON file in Excel? In Excel for Windows, use Data → Get Data → From File → From JSON, which turns the records into a table. Folders shows and edits JSON as text but doesn’t convert it into a spreadsheet.

Is a JSON file safe to open? JSON is data, not a program, and Folders never runs anything. A .har file is the exception to “harmless to share”: it can contain your cookies and login tokens. Send it only to the support team that asked, and delete it afterwards.

JSON vs JSONC vs JSON5: what’s the difference? JSON is the strict standard. JSONC adds comments. JSON5 adds comments plus friendlier syntax such as unquoted keys and trailing commas. Tools that expect plain JSON reject the other two.

Can I open a JSON file on Android? Yes. Install Folders and tap the file; it opens in the text editor, where you can format, search and edit it.

More data formats: how to open YAML and TOML files and how to open KML and GPX files, or see all 382 file types Folders opens.