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OUTPUT
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Beautify, minify, validate and convert JSON — flag lines, your JSON never leaves your browser
CTRL+ENTER format CTRL+F findJsonSilk formats, validates and minifies JSON entirely in your browser — and lets you flag the lines you are working on, so you never lose your place in a long file. It is built around a single goal: working with JSON should feel effortless.
Click any line number and it gets a mark. The header keeps a count, and prev and next jump you between marked lines, so you can move through the places you care about without scrolling past everything in between. Clear wipes them all when you are done, and the marks survive your edits.
It is a scratch annotation layer for a document you will only have open for ten minutes: the lines you have already fixed, the ones you still need to check, the three values a colleague asked about. Working through a long config file without losing your place is the thing this tool was built to make easy, and it is the part we would miss most if it were taken away.
There is no server. JsonSilk is a static page: the parsing, formatting and converting all happen in the tab you have open, on your own machine. No account, no sign-up and no upload step.
You do not have to take our word for it. Open your browser's developer tools, switch to the network panel, then paste a payload and format it: nothing is sent. Or disconnect from the network entirely and keep working — everything still runs, because there is nothing on the other end to talk to.
What is kept locally, and only locally: your theme choice, your indent and sort preferences, and whether you have seen the demo. Those live in your browser's own storage so the page remembers them next time. They never go anywhere. That is the whole list — we would rather tell you exactly what is stored than claim nothing is.
Each pane has its own search box, so you can look for different things on each side at the same time. Matches are highlighted inline, with a counter and up/down navigation — and the line numbers of matching rows light up in the gutter, so you can see where the hits are without scrolling to them. In a nine-hundred-line document that turns "where is this key" from a hunt into a glance.
Format re-indents with two spaces, four spaces or tabs; the beautified output can also have every object's keys sorted recursively, which makes two versions of the same payload easy to diff. Minify strips all whitespace to a single line, with an optional wrap so you can read it without scrolling sideways. Syntax errors report the line, the column and the actual reason — trailing comma is not allowed in JSON, single quotes are not valid in JSON — and clicking the message jumps your cursor straight to the character. While the input is broken the last valid output stays on screen instead of blanking out.
JsonSilk uses its own parser rather than the browser's JSON.parse,
so every value is written back exactly as you typed it. A twenty-digit integer
stays intact instead of silently rounding, 1e400 stays
1e400 instead of turning into null, and escape sequences
are not rewritten. If you are inspecting API payloads, financial records or IDs
that happen to look like big numbers, this is the difference between reading your
data and reading a lossy copy of it.
The output pane has three views and they share one search box. Text is the formatted JSON. Tree collapses and expands so you can take in the shape of a document without reading every value; searching marks the branches that have matches inside, and leaves the expanding to you. Table lays an array of objects out as rows and columns — the same projection the CSV download uses, so what you see is exactly what you would save.
Download saves the formatted JSON, or converts it first. CSV output carries a
UTF-8 byte order mark so Excel opens it without mojibake. XML output sanitises
element names that JSON allows but XML does not, keeping the original key in a
name attribute so nothing is lost. The table view shows you the same
projection the CSV uses, so you can check it before you save.
A tool earns its place through details. The pause before re-formatting grows with the size of your document, so it never fights your typing. Line numbers re-align themselves when a minified line wraps. Your last valid output stays on screen while you fix a syntax error, rather than the pane going blank. Clicking an error message puts the cursor on the exact character. One button sends the formatted output back into the input pane, so you can carry on editing it instead of copying between panes. None of these are headline features — together they are what we mean by silk, and they are the part of the product we keep coming back to.