Lowercase Converter

Overview

Converts text to lowercase instantly, keeping spaces, punctuation and line breaks exactly where they were. The page opens in lowercase mode, and the same panel can switch to UPPERCASE, Title Case, Sentence case, camelCase, PascalCase, snake_case, CONSTANT_CASE, kebab-case or a URL slug without retyping your input.

How It Works

Paste or type into the Input box and the lowercase version appears in the Output Result panel as you type. Because the output is always recomputed from the original input, you can click another case button to compare styles and then click lowercase again to come back. Copy Text copies the result and Clear empties the input box.

Step-by-Step Usage Guide

1. Paste your text into the Input box.
2. Read the lowercase result in the output panel; it updates on every keystroke.
3. Use url-slug instead if the result must be safe to put in a URL.
4. Click Copy Text to copy the result.

Technical Specifications & Standards

Lowercasing uses the browser's toLowerCase, the Unicode default case mapping, which covers far more than the English alphabet: accented Latin letters, Greek, Cyrillic and Armenian all convert. Two details are easy to miss. First, Greek capital sigma has two lowercase forms, σ inside a word and ς at the end, and modern browsers pick the final form at word ends, so the output is real Greek rather than a letter-by-letter substitution. Second, the default mapping is not right for Turkish. In Turkish the capital I lowercases to dotless ı, and dotted İ lowercases to i; a language-neutral lowercase turns I into i, which spells a different word. If you are processing Turkish text, use the Title Case tool, which has a tr locale setting. Lowercase is also the usual first step in normalising data before comparing it, for example when you deduplicate a list of email addresses or tags. It only normalises case, though: it does not strip accents, so café and cafe stay different strings. If you need ASCII-only output for a URL, use the url-slug button, which lowercases, removes accents and replaces everything except letters and digits with hyphens. The kebab-case and snake_case buttons sit between the two: they lowercase and join words with a separator, but keep non-English letters instead of stripping them.

Targeted Use Cases

• Fixing text that was typed with Caps Lock left on.
• Normalising email addresses, usernames or tags before deduplicating them.
• Preparing lowercase file names, CSS class names or database keys.
• Toning down an all-caps title pasted from a PDF before capitalising it properly.

Notes & Gotchas

• Lowercase both sides before comparing strings case-insensitively, rather than lowercasing only one of them.
• Do not lowercase passwords or other secrets, because case is part of their value.
• Use the url-slug mode for URLs, because plain lowercase keeps spaces and accents.
• For Turkish text, use a locale-aware tool so I and İ convert to the correct letters.

Frequently Asked Questions