Case Converter

Input

17 graphemes17 code points17 bytes

Letter case

Live result

CONVERT THIS TEXT

Good fit

Use this tool when

You need to normalize inconsistent casing.
You want to compare the same text in different cases.
You are preparing a heading or a plain lowercase key.

Keep the original

Avoid it when

You need editorial title case with lowercased small words.
Acronyms or proper nouns must stay as typed.
Case is meaningful, such as in code identifiers.

Reviewed truth vectors

Examples that expose the edge cases

InputConvert This Text

OutputCONVERT THIS TEXT

UPPERCASE mode.

InputConvert This Text

Outputconvert this text

lowercase mode.

Inputconvert this text

OutputConvert This Text

Title Case mode capitalizes each word.

Transparent implementation

How it works

01
Choose a case mode with the control above the result.
02
Apply locale-aware upper, lower, or title casing.
03
Preserve non-letter characters and spacing.

Known limitations

What the result cannot promise

Title Case mode capitalizes every word, without editorial exceptions.

Acronyms are not preserved in lower or title modes.

Only letter case changes; spacing and symbols are untouched.

Questions before copying

Frequently asked questions

Which cases are supported?

UPPERCASE, lowercase, and Title Case. Choose one with the control above the output.

Is the conversion locale-aware?

Yes. It uses locale-aware casing so accented and non-English letters convert correctly.

Does it change punctuation or spacing?

No. Only letter case changes; everything else is preserved.

Experience, expertise & trust

How we verify this tool

GlyphSift Editorial — Text-engine authors & reviewers

The GlyphSift Editorial team designs the deterministic text engine, writes each tool's examples against real Unicode edge cases, and reviews every claim before a page becomes eligible for indexing. We build and test the software we document; we do not outsource the copy to generic content mills.

Each tool page is reviewed against the same six input classes the engine is tested with — ASCII, emoji, combining marks, non-Latin scripts, empty input, and 5,000-grapheme input — and cannot become eligible if it is only a parameter variation of another page.

Automated evidence

Tool-contract & coverage suite30 deterministic cases
tests/tools-30.test.mjs mirrors the ToolRunner dispatch and asserts every registered engineId returns the contracted output shape, plus a coverage guard so no tool silently drops characters.
Run in: node --test after a production build (vinext build)
Rendered-HTML suite12 deterministic cases
tests/rendered-html.test.mjs renders the deployed server bundle and asserts the Unicode-version manifest and each wave's tool markup are present in the server-rendered HTML.
Run in: node --test against the built dist/server bundle
Transform & cleanup suite21 deterministic cases
tests/transform-cleanup.test.mjs exercises each deterministic cleanup and transform action against whitespace, duplicate, ordering, casing, and HTML-to-text edge cases.
Run in: node --test, no network, no randomness

Standards this tool follows

UAX #29: Unicode Text Segmentation
Grapheme and word boundaries underpinning line and whitespace operations.
UAX #14: Unicode Line Breaking Algorithm
Line-break semantics behind hard-wrap repair.