About Case Converter Online

Case Converter Online is a free collection of more than 100 text tools. The best known is the case converter, which changes the capitalization of any text to UPPER CASE, lower case, Title Case, Sentence case and nine other writing and code styles. Around it sit tools for counting, cleaning, sorting, formatting, encoding and styling text, all on one site and all free to use.

Why this site exists

Fixing text is a small job that comes up all the time. Someone leaves caps lock on and a whole paragraph has to be retyped. A headline needs proper title case before it goes live. A spreadsheet export is full of stray line breaks. A list of column names has to become camelCase for a program. None of these is hard, but each one is slow and fiddly to do by hand.

Many online tools for these jobs are slow to load, ask you to sign up, limit how much text you can paste, or send your text to a server you know nothing about. This site was built to do the opposite: open quickly on a phone or a laptop, do the job in a few seconds, keep your text on your own device, and then get out of your way.

What you can do here

• Change capitalization. Convert between 13 cases, including sentence case, title case and upper to lower case, with undo and redo.
• Count and analyse text. Count words, characters and sentences with the sentence counter, or find the most used words with the word frequency counter.
• Clean up text. Remove line breaks, delete duplicate lines, strip formatting and special characters, or read text out of an image.
• Style text for social media. Make bold, italic, gothic, small, bubble and upside-down text for Instagram, WhatsApp, TikTok and Discord.
• Format and convert code and data. Tidy up JSON, HTML, CSS, JavaScript, YAML and XML with the formatters, turn CSV into JSON, or convert PDF and Word files into Markdown.
• Encode, decode and generate. Work with Base64, URLs, binary and classic ciphers, and create QR codes, hashes, strong passwords and random values.

Every tool is listed, grouped by job, on the all tools page.

How it works

Every tool on this site runs inside your web browser. When you paste text, open a file or press a button, the work is done by code on your own device. Your text and files are not uploaded to a server, so there is nothing for us to store, read or lose. This also means the tools keep working on a slow connection once the page has loaded, and that large files do not have to travel across the internet and back.

The one exception is the image to text converter, which downloads its reading engine and language data the first time you use it. Even then, the image itself stays on your device. The privacy policy lists exactly what is stored in your browser, what our host, analytics and advertising partners can see, and how to opt out.

How the tools are built and checked

Text conversion looks simple until you meet the edge cases. Title case has to leave short words such as "of" and "the" in lower case, but not at the start of a title or after a colon. Sentence case must not treat the full stop in "e.g." as the end of a sentence. A character counter has to count an emoji with a skin tone as one character, not four. Accented letters, German and French quotation marks, Japanese and Korean text all need their own rules.

Each tool page explains the rules that tool follows, with examples taken from the tool itself rather than written by hand. Behind the pages, the conversion code is covered by several hundred automated tests that run before every update, so a fix in one place does not quietly break something elsewhere. When a reader reports a result that looks wrong, the case is added to those tests once it is fixed.

Automatic tools still have limits. A case converter cannot know that a word is a brand name that should keep its unusual capitals, and a citation generator can only format the details you give it. Please check the result before you publish it or hand it in.

Available in eight languages

The site is available in English, Spanish, French, German, Italian, Portuguese, Japanese and Korean. Translated pages are written for readers of that language, with examples and rules that fit it, such as the capitalization of German nouns or the spacing around French punctuation. Use the language menu at the top of any page to switch.

Free to use

All tools are free for personal and commercial use. There is no account to create, no trial period and no limit on how many times you can use a tool. To cover hosting and development costs, the site may show advertising on some pages. The tools themselves stay the same for every visitor.

Feedback

Found a result that looks wrong, or want a tool that is missing? Write to [email protected]. A short example of the text you entered and the result you expected is the most helpful thing you can send. The contact page explains what to include for each kind of message.