How to view a JSON file

To read a JSON file, open it in a browser (drag it into a tab), a code editor like VS Code, an online viewer, or the command line with jq — the right choice depends on the file’s size, how confidential it is, and whether you need to search it or just look at it.

Pick by what you have

1. Drag it into a browser

Every modern browser renders a local .json file. Firefox has the best built-in viewer — a collapsible tree with filtering, no extension required. Chrome and Safari show raw text unless you install one.

1. Open a new browser tab
2. Drag the .json file onto it, or press Ctrl+O (Cmd+O on a Mac) and choose the file

Good for: a quick look, with nothing to install and nothing leaving your machine. Bad for: anything large, and any file whose one long line you actually need to read — Chrome and Safari will show it exactly as it is.

2. A code editor

VS Code, Sublime Text and their peers all handle JSON well: syntax highlighting, folding, and a format command that turns one long line into something readable. In VS Code that is Shift+Alt+F, or Shift+Option+F on a Mac.

Good for: files you are going to edit, and anything sensitive — it never leaves your machine. Bad for: a file you only want to glance at, if the editor is not already open. Very large files will also make most editors struggle.

3. The command line, with jq

jq is the right answer more often than people expect. It formats, filters and transforms, it streams rather than loading everything into memory, and it composes with everything else in a shell.

# Pretty-print
jq . data.json

# Just the names
jq '.users[].name' data.json

# Filter, then reshape
jq '.users[] | select(.age > 30) | {name, city: .address.city}' data.json

# Is it even valid?
jq empty data.json && echo "valid"

Good for: large files, anything repeatable, and any transformation. It is the only option here that scales to gigabytes. Bad for: getting an overview of a document whose shape you do not yet know — and it has a real learning curve.

4. An online viewer

Useful when you want a structural view without installing anything, and when a tree is not the reading you need — a table, a graph or a chart can answer a question faster.

The question to ask first is whether the tool uploads your file. Many do, because parsing on a server is simpler to build, and most do not say so clearly. You can check: open your browser’s network panel, load a file, and watch for a request carrying it. The stricter test is to disconnect from the network — a genuinely client-side tool keeps working.

Good for: a fast structural overview, and views a text editor does not have. Bad for: very large files, and — if the tool uploads — anything confidential.

Open a JSON file hereParsed in your browser. Nothing uploaded.

5. A browser extension

Extensions like JSON Formatter intercept every JSON response as you browse and render it as a tree automatically. If you spend your day reading API responses in a browser, this is the highest-leverage option on this page.

Good for: API work, continuously. Bad for: a one-off file, and worth remembering that an extension with permission to read page content is a meaningful amount of trust.

6. Python, if it is already installed

python -m json.tool data.json

# Or, keeping key order and handling non-ASCII properly:
python -c "import json,sys; print(json.dumps(json.load(open('data.json')), indent=2, ensure_ascii=False))"

Good for: formatting on a machine where installing jq is not worth it. Bad for: anything beyond formatting.

When the file will not open

It says the JSON is invalid

Something is genuinely malformed. Use a viewer that reports the position rather than only the fact — the usual culprits are a trailing comma, a missing closing brace, or single quotes where JSON requires double.

It opens blank, or the tab hangs

The file is probably too large for the tool. Check its size; above a few hundred megabytes, use jq or a streaming parser rather than anything in a browser.

Each line is a separate object

That is JSON Lines, not JSON — one complete value per line with no enclosing array. It is a different format, common for logs. jq reads it natively; a strict JSON parser will reject it.

It is one enormous line

Perfectly valid, just minified. Any formatter will fix it: jq ., your editor’s format command, or any viewer.

The text is mojibake

An encoding mismatch. JSON should be UTF-8; a file saved as UTF-16 or Latin-1 will look like garbage in a tool assuming otherwise.