Case Converter

Paste your text, preview the conversion instantly, then copy, download, or apply the result to Original. Everything runs locally in your browser—nothing is uploaded or sent to a server.

Original

0 words0 characters

Converted

0 words0 characters

Text cleanup

Optional. Applies to the converted result only—not your original text.

Fixed spellings (title case)

Optional. Title case only. Set exact spellings (e.g. iOS, API)—not a lowercase word list.

How to use

About this tool

Turn English text into the format you need in seconds. Original holds your source text; Converted shows a live preview. Pick a format, check the result, then copy, download, or apply back to Original.

Beyond basic upper- and lowercase, ToolGee supports common developer naming styles, optional text cleanup, and a customizable title case word list—useful for headings, variable names, URL slugs, meta titles, and UI copy.

How to use

Paste or type your text in Original
Choose a format under Writing or Developer
Review Converted; turn on cleanup or fill in the title case word list if needed
Copy, Download, or Apply to Original to keep editing

Supported formats

Writing

Format	What it does
UPPERCASE	All letters capitalized
lowercase	All letters lowercase
Sentence case	First letter of each sentence capitalized
Title case	Heading style; built-in minor words; custom fixed spellings
Capitalized case	First letter of every word capitalized
Swap case	Uppercase ↔ lowercase reversed

Developer

For variables, API fields, database columns, and URL slugs:

Format	Example (from `hello world`)
camelCase	helloWorld
PascalCase	HelloWorld
snake_case	hello_world
kebab-case	hello-world
CONSTANT_CASE	HELLO_WORLD
dot.case	hello.world.example

Text cleanup (optional)

Applied to Converted only:

Trim spaces
Remove extra spaces
Remove empty lines
Normalize whitespace
Remove line breaks (merges lines—use when you mean it)

Fixed spellings (title case, optional)

Under the Writing tab, expand the list and enter words that need a fixed display in headings (comma, space, or line-separated). Title case only. Type the casing you want (e.g. `iOS`, `API`)—not a lowercase word list. Matched words are output exactly as entered, with priority over default rules. Built-in minor words stay lowercase mid-title automatically—you usually do not need to add them.

These words are lowercased in the middle of a title (first and last words stay capitalized; fixed spellings in your list take priority):

a	about	above	after	an
and	as	at	before	below
between	but	by	down	during
for	from	in	into	nor
of	off	on	or	out
over	per	so	than	the
through	to	under	up	via
vs	with	without	yet

Why use ToolGee's case converter?

Instant preview — See results as soon as you pick a format; no extra clicks.
Original stays put — Switch formats anytime; use Apply to Original when you are ready.
Download export — Save long results as .txt without relying on copy alone.
Formatting preserved — Line breaks stay intact during case conversion.
Private by default — Processing happens locally; nothing is uploaded.
Built for developers too — Switch naming styles in one click.
Works on mobile — Responsive layout with touch-friendly controls.

Common use cases

Fix text typed with Caps Lock on
Clean up essay, article, and email subject lines
Rename variables or fields in bulk (line by line)
Create kebab-case URL slugs
Standardize meta and page titles
Tidy extra spaces and blank lines from pasted text
Keep UI copy and product docs consistent

FAQ

Q: What is a case converter?: A: A case converter changes English text into different capitalization or naming styles—such as ALL CAPS, lowercase, title case, sentence case, and developer formats like camelCase and snake_case. ToolGee runs entirely in your browser. No sign-up required.
Q: Which formats are supported?: A: You can convert between:
Writing styles: uppercase, lowercase, sentence case, title case, capitalized case, swap case
Developer naming: camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case
Text cleanup (optional): trim spaces, remove extra spaces, remove empty lines, normalize whitespace, remove line breaks
More formats will be added over time.
Q: Does title case handle words like "a", "an", and "the"?: A: Yes. Title case includes common English minor words (such as a, an, the, and) and keeps them lowercase in the middle of a heading. You can also set fixed spellings under Fixed spellings (title case)—e.g. iOS, API. Matched words appear exactly as you entered, with priority over default rules. If your school, publisher, or client has a specific style guide, follow their rules.
Q: Can I customize how specific words appear in title case?: A: Yes. Under the Writing tab, expand Fixed spellings (title case) and enter words with the casing you want (e.g. iOS, API)—not a lowercase word list. Applies only when Title case is selected; matched words are output exactly as entered. Your list is saved locally in the browser.
Q: Will my line breaks be removed?: A: Not by default. Case conversion keeps your line breaks and only changes letter casing. If you turn on "Remove line breaks," the result may become a single line—your original text stays unchanged. Leave that option off when you need paragraphs.
Q: What is the difference between Original and Converted?: A: Original is where you paste or type your text. Converted shows a live preview of the selected format, ready to copy or download. When you switch formats, the preview updates from Original so you can compare options easily.
Q: What does Apply to Original do?: A: It copies the current Converted preview (including any cleanup options) back into Original so you can keep editing or try another format. Your previous Original text is saved for Undo.
Q: Can I download the converted text?: A: Yes. Click Download to save the current Converted preview as a .txt file—handy for long text or line lists. The file is created locally; nothing is uploaded.
Q: Can developer naming handle mixed input like user_name or userName?: A: Yes. The tool recognizes words separated by spaces, underscores, hyphens, or mixed casing, then converts them to your chosen naming style.
Q: How do the cleanup options work?: A: Pick a case or naming format first, then check any cleanup options you need. Cleanup applies to the Converted preview only—not to Original.
Q: Is my text uploaded to a server?: A: No. Everything runs locally in your browser. To help you pick up where you left off, a draft may be saved on your device. You can clear site data in your browser settings at any time.
Q: Can I convert long text or multiple lines at once?: A: Yes. Paste as much as you need. Title and sentence case work line by line or sentence by sentence. Developer naming converts each line separately—handy for lists of field names or titles.
Q: Is there a character limit?: A: You can enter up to 100,000 characters at a time. Very long text may feel slower on some phones—splitting it into smaller chunks can help.
Q: Does it support find and replace?: A: Not yet. For most jobs, case conversion plus cleanup options is enough.
Q: Does it work on mobile?: A: Yes. On phones, Original appears above Converted, with Copy, Download, Apply to Original, Clear, and Undo at the bottom.
Q: Is ToolGee Case Converter free?: A: Yes. All core conversion and cleanup features are free—no registration needed.