Why this tool is useful
Use HTML Formatter when you need to make pasted HTML easier to inspect by placing nested tags on readable indented lines. The result is immediate and easy to verify before you reuse it.
Developer & Data ยท runs locally
HTML Formatter
make pasted HTML easier to inspect by placing nested tags on readable indented lines.
Ready. Your working data stays in this browser.
How it works
Enter the values requested by HTML Formatter. The browser validates the input, performs the calculation locally and produces a copyable result with clear errors.
Practical example
A practical use is to run HTML Formatter on a small sample first, confirm the output, and then process the complete value or list.
Validation
The calculation is deterministic and explains validation errors instead of silently changing invalid input.
Privacy boundary
Input and output remain in this tab. Copy and download happen through browser APIs without a server upload.
Result passport
Every run reports its tool mode, timestamp and input/output size so transformed data can be audited.