Format and validate JSON.

Yes. Formatting, the tree, Copy and Download need no account and cost nothing. Publishing with Get a link is free as well, with or without an account.

Not while you format. Parsing, formatting, the tree and the file picker all run in this page. Your JSON goes to NudgeHost only when you press Get a link to publish it.

Yes. The output pane names the first problem with its line and column, such as "Line 4, column 6: Trailing comma before ]", and the input marks the same spot in its gutter. Fix that one and the next problem, if there is one, shows up in its place.

No. The formatter follows the JSON standard strictly, so comments, trailing commas, single quotes, unquoted keys, NaN and Infinity are all reported as errors with their line and column. JSON.parse and other strict readers reject them too, so a file that passes here will load elsewhere.

A string opened with a double quote never closes before the end of its line or the end of the input. JSON strings cannot run onto a new line, so a line break inside one has to be written as \n.

Yes. A single string, number, true, false or null is valid JSON on its own, and the formatter prints it as it is. Most JSON starts with { or [, and that is where the indenting makes a difference.

It is skipped. Some editors put an invisible byte order mark at the start of a file, and it is not part of the JSON. Anything else before the first value is reported as an error, with its line and column.

Yes. Each number is printed from the text you gave it, so 12345678901234567890 stays 12345678901234567890 and 1.50e+10 stays 1.50e+10. A tool that reads JSON with JavaScript's JSON.parse turns any integer past 2^53 into the nearest double, which changes its last digits.

No. Strings are printed exactly as written, escapes included, so \u00e9 stays \u00e9 rather than turning into é. Only the whitespace between values changes, and the key order when Sort keys is on.

Yes. Tick Minify and the output drops to one line with no spaces between values. The numbers and strings stay exactly as written, and Sort keys still works.

Yes. Pick 2 spaces, 4 spaces or tabs from the menu above the output. The formatter remembers your choice in this browser.

No. Sort keys moves keys only within their own object, and Minify only removes the whitespace between values. Every key, value, number and string is still there, written exactly as before, and the JSON standard treats the order of an object's keys as carrying no meaning.

It puts the keys of every object in order, at every level of nesting, comparing them character by character, so capital letters come before lower-case ones. Arrays keep their order, since the position of an item is part of what it means.

They are kept, in the order they appear. The JSON standard allows a key to repeat, and the formatter does not pick one over the other. With Sort keys on, repeated keys stay next to each other in their original order.

The Tree tab shows the same result as a tree you can fold and unfold. The top two levels start open, and a large array opens 200 items at a time, with a button for the next batch.

Yes. Use Open file, or drag a .json or .txt file onto the input. The formatter opens files up to 10MB, the same limit as the JSON viewer, and Download saves the result under the same name with .json on the end.

Files up to 10MB open, and pasted text has no set limit. Input over 200,000 characters is formatted after a short pause in typing, away from the page's main thread, so the page keeps responding while a large document is laid out.

Undo and redo work as they do in any text box, Tab indents the selected lines and Shift+Tab takes the indent away. The small arrows beside the line numbers fold an object or an array out of sight, in the input and in the output.

Yes. The output pane cannot be typed in, but you can select any part of it and copy that. The Copy button above the editors takes the whole output.

Yes. The moon button switches both editors to a dark theme, and this browser remembers the choice. It is the same setting the HTML tester uses.

No. The JSON lives in this page until you leave it, and reloading brings back the sample. Use Download to keep a copy as a .json file, or Get a link to put it online. The formatter remembers only your indent and whether you chose the dark editor.

Press Get a link. The formatted JSON is published as a .json file at a nudgehost.com address, and the Copy link button puts the address on your clipboard, ready to paste into a chat, a ticket or an email.

No. Get a link, Copy and Download stay switched off until the input parses, so whatever you save or share is valid JSON, laid out the way the output pane shows it.

The name of the file you opened, with .json on the end, or data.json when you pasted the JSON. That name shows above the tree on the link and on its preview card.

The JSON opens as a collapsible tree, with buttons to copy the raw text or download the file. Chat apps that show link previews draw a NudgeHost card with the file name. A file over 10MB opens as a download instead of a tree.

7 days without an account. On a free account it stays up until you delete it, and signing up in the same browser moves the links you made without an account across.

3 live at a time. When one expires, its slot frees up. A free account holds 10, and Pro and Studio have no limit on live links.

The JSON viewer opens a file and shows it as a tree to read. The formatter is for working on JSON. It re-indents it, checks it, sorts or minifies it, and can publish the result. Both read files in your browser.