Case Converter — Free Online Tool
Use instantly, free, with no signup. Your files are processed locally and never uploaded.
By the AllFileBox Team · Last updated: 2026-06-21
Case Converter is a free online tool that instantly changes text between uppercase, lowercase, title case, and sentence case in your browser, so you can fix capitalization without retyping.
Why change text case
Pasted text often arrives in the wrong case: a heading typed in all caps, a sentence stuck in lowercase, or a title that needs each word capitalized. Retyping it is slow and error-prone. A case converter transforms the whole block in one click, which is invaluable for cleaning up imported data, formatting headings, and fixing accidental caps-lock typing.
The main case styles
Uppercase makes every letter capital, lowercase makes them all small, title case capitalizes the first letter of each word for headings, and sentence case capitalizes only the first letter of each sentence. Some converters add extras like alternating case or capitalized first letters. Each style suits a different need, from shouting a label to formatting a proper title.
Working with large blocks
Because the transformation is a simple rule applied to every character, even a long document converts instantly. You can paste thousands of words, switch the entire block to sentence case, and copy the result back in seconds. This makes the tool handy for tidying up spreadsheet exports, code comments, and bulk content before publishing.
Private and local
Case Converter runs entirely in your browser. Your text is transformed locally and is never uploaded or stored, so confidential content stays private. There is no server involved, the conversion is instant, and closing the tab clears the text from memory.
How To Use Case Converter
- Open the Case Converter tool.
- Type or paste your text into the box.
- Choose the case style you want.
- See the converted text update instantly.
- Copy the result to use anywhere.
Fix an all-caps paste
Fix an all-caps paste
Drop in text that arrived in shouting capitals and convert it to sentence case in one click.
Format a heading
Switch a line to title case so each important word is capitalized for a clean heading.
Clean imported data
Convert a column of mixed-case entries to a consistent lowercase or title case before using it.
| Style | Example input | Result |
|---|---|---|
| UPPERCASE | hello world | HELLO WORLD |
| lowercase | Hello World | hello world |
| Title Case | hello world | Hello World |
| Sentence case | hello world | Hello world |
Related Tools
Key Features Case Converter
Your Files Stay Private
All processing happens in your browser using WebAssembly. Your file is never sent to our servers. We have zero access to your files — guaranteed.