Code & Data
Explore JSON as a tree, not a wall of text
Paste JSON and explore it by folding and unfolding. Formatted text is readable until it is four thousand lines long — at that point the question is what shape the document is, and only collapsing answers it.
- Runs in your browser
- No account required
- Free to use
How it works
The first two levels open by default
Enough to see the top-level structure without scrolling, and shallow enough that a large document does not render thousands of rows before you have looked at it. Everything deeper opens on a click.
Types are coloured, and counts are shown
Strings, numbers, booleans and null are visually distinct, so a number that arrived as a string is obvious rather than something you have to squint for. Each object and array shows how many entries it holds while collapsed.
What it does
Fold and unfold anything
Click any container to collapse it. Reading a 5,000-line API response becomes a matter of opening the three branches you care about.
Values coloured by type
The commonest data bug is a number or boolean that arrived as a string. Colour makes it visible without reading the quotes.
Structure summarised
Key, object and array counts plus nesting depth, so you know the scale of what you are looking at.
Your data never leaves the page
API responses, config files and exports are exactly the sort of thing that should not be pasted into someone else’s server. Parsing happens in your browser and what you paste is never transmitted — there is no code here that could send it anywhere, even by accident.
Practical advice
Getting a better result
- Collapse the top-level array first when looking at a list response — the shape of one item usually tells you everything.
- Watch for numbers rendered in the string colour. An ID that arrived as "1234" rather than 1234 breaks comparisons in ways that are hard to trace.
- For editing rather than reading, the JSON formatter re-indents and can sort keys.
Questions
Things people ask
Can it handle a large file?
Yes, within your device’s memory — it runs in the browser. Only the branches you have opened are rendered, so a large document stays responsive as long as you do not expand all of it at once.
Is my data uploaded?
No. The document is parsed and rendered in your browser, and the page makes no network requests. Nothing is stored or logged.
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Open toolWho builds these
Free tools by day. Websites that earn their keep by trade.
KuConvert is built by KUDUY, a web design and development agency. From custom WordPress builds to SEO and e-commerce, everything they do is engineered to bring you more qualified traffic and turn it into revenue.
Web Design
Custom, conversion-focused web design that captivates visitors and turns them into paying customers. Mobile-first, fast, and built to rank.
Web Development
Custom WordPress websites built with clean code, blazing-fast performance (Core Web Vitals optimised), and enterprise-grade security.
E-Commerce
Online stores that convert visitors to customers with seamless shopping experiences.
SEO
Technical SEO, keyword research, on-page optimisation and local SEO strategies that drive qualified organic traffic.
Digital Marketing
Data-driven campaigns that deliver measurable ROI across every channel.
Branding
Memorable brand identities that stand out in any market and build lasting trust.
Website Help
One-on-one expert support for bug fixes, updates and ongoing maintenance — without a long-term retainer.
Fixed scope, no surprise invoices
Most sites ship in four to eight weeks with the scope and the price agreed up front.
SEO from day one
Search is designed into the build — structure, schema and Core Web Vitals — not retrofitted.
A team, not a ticket queue
A project manager, a designer and a developer you can actually reach.
Need your whole site to load this fast?
Images are usually the heaviest thing on a page and the easiest win. KUDUY works on site speed, image delivery and Core Web Vitals for teams who would rather not do it by hand.
This tool runs entirely in your browser. Your files are never uploaded.