Lowercase to Uppercase Converter — Text Case Changer
Paste any text and convert it to UPPERCASE, lowercase, Title Case, Sentence case, or alternating case in one click. Also shows character count, word count and letter statistics.
Conversion mode
How does this calculator work?
UPPERCASE uses toUpperCase() on every character; lowercase uses toLowerCase(). Title Case capitalises the first letter of each word; Sentence case capitalises the first letter after sentence-ending punctuation. Alternating case toggles upper/lower for each letter. No install needed — instant, client-side.
Formula
How this is calculated
Text case conversion is a straightforward character-level operation. Uppercase replaces every letter with its capital form using the Unicode to-upper-case mapping. Lowercase applies the reverse. These operations are locale-aware in most languages: for example, the German sharp-s (ß) becomes "SS" in uppercase.
Title case capitalises the first letter of every word boundary (\b\w pattern). This is a simple rule; professional style guides vary — some exclude prepositions and articles from capitalisation, but those rules are language- and publication-specific and are not applied here.
Sentence case capitalises the first letter of each sentence detected by a period, exclamation mark, or question mark followed by whitespace. Alternating case toggles the case of each alphabetic character in sequence, producing the "sponge-bob mocking text" pattern used in internet culture to express sarcasm. All modes leave digits, punctuation, and whitespace untouched.
Frequently asked questions
Yes — the converter uses JavaScript's built-in toUpperCase() and toLowerCase(), which handle most Unicode Latin-script accented characters (é→É, ü→Ü, etc.) correctly. However, some scripts have complex casing rules (e.g., Greek final sigma σ/ς) that simple regex-based title/sentence-case may not fully respect.
Title Case capitalises the first letter of every word. Sentence case only capitalises the first letter of the first word in a sentence (after a period, exclamation mark, or question mark). "The quick brown fox" → Title Case: "The Quick Brown Fox"; Sentence case: "The quick brown fox."
Yes — the result is displayed in the Converted text card. Select and copy it with Ctrl+C / Cmd+C, or use the copy button if your browser shows one on the text element.
Also known as
TG we-Calculate Editorial Team. (2026). Lowercase to Uppercase Converter — Text Case Changer [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/lowercase-to-uppercase-converter
TG we-Calculate Editorial Team. "Lowercase to Uppercase Converter — Text Case Changer." TG we-Calculate. 2026. https://we-calculate.com/calculator/lowercase-to-uppercase-converter.
TG we-Calculate Editorial Team, "Lowercase to Uppercase Converter — Text Case Changer," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/lowercase-to-uppercase-converter
@misc{wecalculate_lowercase_to_uppercase_converter, title = {Lowercase to Uppercase Converter — Text Case Changer}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/lowercase-to-uppercase-converter}}, year = {2026}, note = {TG we-Calculate} }
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