Instantly convert text case with one click. Supports four modes: uppercase, lowercase, title case, and sentence case.
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When you need to standardize the case formatting of text in documents, code, or data, manual editing is both time-consuming and error-prone. This tool converts English letter cases based on the Unicode standard, processing all English characters (a-z, A-Z) within the ASCII and Unicode ranges. It accurately outputs four formats: UPPERCASE, lowercase, Title Case, and Sentence case.
Q: Does the case converter support Chinese characters?
No. This tool is designed specifically for English letters. Chinese characters and other non-alphabetic scripts will be output exactly as entered.
Q: What is the difference between Title Case and Sentence case?
Title Case capitalizes the first letter of every word (e.g., "The Quick Brown Fox"), while Sentence case only capitalizes the first letter of each sentence (e.g., "The quick brown fox."). The former is ideal for headings, while the latter follows standard writing conventions.
Special symbols and numbers are not affected by the conversion. For very long texts, batch processing is recommended. Note that Title Case does not automatically apply specific capitalization rules for articles, prepositions, or other special words.
In programming, it is recommended to use UPPERCASE for naming constants (e.g., MAX_LENGTH) and camelCase for variable names (e.g., userName). Typical input/output examples:
Input: "hello WORLD! 123"
• Uppercase → "HELLO WORLD! 123"
• Title Case → "Hello World! 123"
