Drop in the raw data
Paste a payload, markup snippet, stylesheet, or text block directly into the matching tool.
100% in-browser developer utilities
Use developer tools on real data without sending it anywhere.
Format JSON, preview HTML, inspect XML, clean JavaScript, convert CSS units, and compare text in one fast workspace built for privacy-first debugging.
- Source data stays in browser memory
- No request queue, no upload step, no server wait
- Keyboard shortcuts across the full suite
100% local processing
Useful for payloads, keys, snippets, and internal markup you do not want routed through a third-party backend.
One suite, six workflows
Jump from JSON cleanup to HTML testing, CSS formatting, or text encoding without changing products.
Made for scanning
Short actions, obvious entry points, and direct tool labels instead of a marketing-heavy homepage.
Tool suite
Start from the task you need to finish.
Each tool is focused, fast, and tuned for common developer cleanup jobs.
JSON Viewer
Format, minify, unescape, inspect in tree view, and convert JSON to YAML.
HTML Sandbox
Preview markup live, test responsive behavior, and open a clean browser tab render.
XML Viewer
Validate structure, pretty-print documents, minify payloads, and convert XML to JSON.
JavaScript Tools
Beautify scripts, minify output, run syntax checks, and test snippets in a sandbox.
CSS Viewer
Format stylesheets, compress CSS, convert px to rem, and review extracted color values.
Text Utilities
Diff text, encode or decode Base64 and URLs, and clean escaped strings quickly.
How it works
A shorter path from raw input to usable output.
The homepage now explains the product as a workflow instead of a keyword pile.
Run one obvious action
Format, minify, preview, convert, diff, or decode with clear controls and shortcut support.
Copy out the result
Take the cleaned output back to your editor, API client, design handoff, or debugging session.
Product reasons
Why developers choose client-side utilities.
Speed is useful, but the bigger win is keeping private material out of server logs and upload pipelines.
Better for sensitive payloads
Paste tokens, config fragments, API responses, or internal markup without routing them through a formatter service.
Faster debugging loops
When there is no upload step, you can inspect, fix, and copy results back out immediately.
Consistent tool language
One interface model across JSON, HTML, XML, JavaScript, CSS, and text utilities reduces learning cost.
Built for repetition
Hotkeys and direct actions make the suite practical for day-to-day cleanup instead of a one-off marketing demo.
What "private" means here
OnlineViewer Dev runs formatting, preview, parsing, and conversion logic in the browser. The core homepage message is now explicit about that behavior instead of leaving it buried lower on the page.
- JSON payloads stay local to your session
- HTML preview runs in your browser, not a remote render service
- Formatting and conversion happen without a backend processing queue
Learn the workflows behind the tools.
FAQ
Common questions before you start.
These answers keep the trust and product model obvious for first-time visitors.
Is my code or data uploaded to any server?
No. The homepage and tool descriptions now lead with local browser processing so visitors understand the privacy model immediately.
Which tool should I open first?
Start with the data type you already have. JSON for payload inspection, HTML for live rendering, XML for document cleanup, JavaScript or CSS for formatting, and Text for diffs or encoders.
Can I test responsive HTML layouts here?
Yes. The HTML sandbox is positioned as a quick preview and responsive testing tool with viewport-based checks.
Ready to use
Open a tool and start with the data you already have.
No signup wall, no handoff to another product, and no extra explanation needed before the first useful action.