Lowercase Converter - Convert Text to Small Letters

Lowercase without surprises

Converting to lowercase is the reverse of uppercase, with its own language rules:

Turkish and Azerbaijani: I → ı (dotless) and İ → i. With the default English rules, “ISTANBUL” would become “istanbul” with a dotted i, which is wrong in Turkish.
Greek: a capital sigma becomes the final form ς at the end of a word and σ elsewhere so ΟΔΟΣ becomes “οδος” with the correct final letter.
Lithuanian: dots are added above i before certain accents.

Pick the language that matches your text; for anything else the default works.

Common uses

Normalising email addresses, usernames and tags before comparing them.
Cleaning up text pasted in capitals before converting to sentence case.
Preparing keyword lists, though the Keyword List Cleaner also deduplicates and tidies spacing.

Worked example

Here is what the Lowercase Converter returns for its built-in example. Settings used: Language rules: Default (English and most languages). Click Try an example in the tool above to load it, then change it as you like.

Input

ISTANBUL İZMİR — ΟΔΟΣ ΣΟΦΙΑΣ — THE QUICK BROWN FOX

Output

istanbul i̇zmi̇r — οδος σοφιας — the quick brown fox

Questions

How do I make all text lowercase?

Paste it into the box. The lowercase result appears instantly, ready to copy or download.

Does it handle non-English letters?

Yes. Accented letters, Cyrillic, Greek and other cased scripts are converted correctly; choose a language for Turkish, Azerbaijani, Greek or Lithuanian rules.

Last reviewed 1 November 2026 · How Textkiln tools work