Frequently Asked Questions

Go to jsonhero.dev, paste your JSON into the editor, and click "Format". Your JSON will be pretty-printed with proper indentation and syntax highlighting. You can also load JSON from a URL or upload a file.

Yes — open the JSON diff page, or click Compare in the editor to take the document you're working on with you. Paste or load the two documents and JSON Hero shows what was added, removed or changed, and where a value changed type (the number 42 becoming the string "42", say), side by side or as a unified diff. Object key order is ignored. You can match array items by a key such as id, compare arrays ignoring their order, ignore noisy paths like $.**.updatedAt, allow a numeric tolerance, and search both documents at once. A compatibility report then flags the changes most likely to break code that reads the data. The comparison runs in your browser, and nothing is uploaded unless you share it. The free plan compares up to 100 KB per side, with up to 3 ignored paths and 1 match-by-key rule; Pro raises that to 1 MB per side, lifts the rule limits, saves rule presets in your browser, and exports a comparison as a JSON Patch, a unified diff or Markdown.

Yes. The editor is free with no sign-up required and no ads. Formatting, minifying, validating, searching, comparing, editing, downloading and sharing all work on the free plan, with documents up to 100 KB. There is also an optional Pro subscription, which raises that limit to 1 MB, lets you choose how long a share link lives, and adds saved collections.

Pro raises the document limit from 100 KB to 1 MB everywhere you work with JSON — formatting in the editor, opening a file, fetching from a URL, share links, and each side of a comparison — lets you choose how long a link lives instead of the fixed 7 days, adds saved collections so you can name, edit and delete your shares, raises the daily share limit from 100 to 500, and gets you priority replies at hello@jsonhero.dev. For comparisons, Pro also lifts the limits on ignore and match rules, saves rule presets in your browser, and exports a comparison as a JSON Patch, a unified diff or Markdown. It costs ₹99 a month or ₹999 a year in India, and $4.99 a month or $49 a year elsewhere. See Pricing for the full comparison, and the Cancellation & Refund Policy for how cancelling works.

From your Billing page, where you can see your plan and payment history, update your payment method, and cancel. Cancelling stops the next renewal: you keep Pro until the end of the period you've already paid for, and you can resume the subscription from the same page before then. Payments are handled by Paddle.com, our online reseller and Merchant of Record, which emails you a receipt for every payment. See the Cancellation & Refund Policy for refunds.

By default your JSON stays on your device. Formatting, minifying, validating, searching, folding, unescaping, comparing and downloading are all done by JavaScript in your browser, and none of that JSON is sent to us. Sharing is the exception: when you click Share, the contents of the editor (or both documents, when you share a comparison) are uploaded to our servers so the link has something to serve, and they are deleted automatically after 7 days on the free plan, or later with Pro. If you never click Share, your JSON never leaves your device.

Clicking Share uploads the text in the editor and gives you a link such as jsonhero.dev/s/AbC123XyZ0. We store the JSON in a private storage bucket, along with its size, a checksum, a short preview snippet, an auto-generated summary such as JSON object · 3 keys, any name you add, a view count, and a salted hash of your IP address used only for rate limiting. No account is needed, and even when you're signed in a share is stored without your name or account — only your plan is recorded, to apply its limits. Everything is deleted 7 days after upload on the free plan, or later with Pro.

Anyone who has the link. Share links are not password protected; their only protection is a random 10-character id that is effectively unguessable. We never list share links in our sitemap, but we do not block search engines from them either, so a link posted somewhere public can be crawled and indexed. Treat a share link as sensitive, and don't share credentials, access tokens, or personal data through one.

Yes. When you paste a share link into Slack, X, Discord or anything else that unfurls links, the preview card shows the start of your JSON — roughly the first 180 characters as the description, plus an image rendered from the opening of the document. That's deliberate, so people can see what they're about to open, but it does mean a snippet of your data is visible to everyone who can see that message.

On the free plan, a share stays live for 7 days from the moment you create it; Pro links last longer. When that time is up, the link reports "Share expired", a daily cleanup job deletes the stored JSON and its rendered preview image, and the id is retired so it's never handed out again. There is no self-serve delete yet — if you need a share taken down sooner, email hello@jsonhero.dev.

Yes — the free plan works with documents up to 100 KB (102,400 bytes) of UTF-8 text. That limit applies wherever JSON enters the editor: formatting what you paste, opening a file, fetching a URL, and creating a share link. Pro raises it to 1 MB. For a comparison, the limit applies to each side. Opening a share link someone sent you is never limited, whatever plan you're on. On the free plan you can also create up to 30 new share links an hour and 100 a day — counted per IP address when you're signed out, and per account when you're signed in. Pro raises the daily limit to 500.

Yes, on any plan. Share on the diff page gives you a link that opens both documents with your comparison rules and the view you were looking at. Sharing uploads both documents, their names and your rules, stored and deleted exactly like a shared document, and anyone with the link can open them. When the link is unfurled in Slack, X or a chat app, the preview shows the two names and the first few changes, values included. A comparison counts as one share against the hourly and daily limits, and follows your plan: up to 100 KB per side with links that last 7 days on the free plan, or 1 MB per side and 30 days with Pro. Opening a comparison someone sent you is never limited by your plan, and sharing one you received without changing it hands back the original link.

Yes. Click the "Minify" button in the toolbar or press Cmd/Ctrl+Shift+M to compact your JSON to a single line, removing all whitespace. This is useful for reducing payload size.

Yes. When you click "Format", JSON Hero validates your input using JSON.parse. If the JSON is invalid, it shows a warning toast and provides best-effort formatting using a tolerant parser so you can still see and fix the structure.

Yes. Click "Load JSON" in the toolbar, enter any public URL in the URL field, and click "Fetch". JSON Hero will download the JSON from that endpoint and display it in the editor. This is great for inspecting API responses.

JSON Hero works in all modern browsers including Google Chrome, Mozilla Firefox, Apple Safari, and Microsoft Edge. It requires JavaScript to be enabled.

Yes. Use the search bar in the toolbar to find text within your JSON document. Matches are highlighted in yellow, and you can navigate between them with the Next/Previous buttons or by pressing Enter. The match counter shows your position in the results.

Click the fold arrow (▶) next to any object or array to collapse it. The collapsed section shows a placeholder like {...} or [...]. Use the "Collapse all" and "Expand all" toolbar buttons to fold or unfold the entire document at once.

Yes. If you paste a JSON string that contains escaped characters (like \"), JSON Hero detects this and offers an "Unescape" button. Clicking it unescapes and re-formats the nested JSON so you can view it properly.

Yes. JSON Hero supports several keyboard shortcuts: Cmd/Ctrl+Shift+M to minify, Enter to jump to the next search match, Cmd/Ctrl+Enter for the previous match, and standard text editing shortcuts in the editor.