About Online Text Editor
The Online Text Editor is a notepad and a code editor in a web page. Open as many tabs as you like and drop in TXT, log, HTML, CSS, JavaScript, JSON, SQL or Python files: words are coloured by language, with line numbers, indent guides, matching brackets and completion. Encodings and line endings are recognised as a file opens — UTF-8, GBK, GB18030, Big5, Shift_JIS, UTF-16 — and if the text looks garbled you can reopen it with another encoding. Saving keeps the file's encoding, or converts it to the one you choose.
The everyday text jobs sit in the side panel. Find and replace takes regular expressions, $1 groups and \U for upper case, shows every changed line before a replace-all, and searches all tabs at once. Line tools sort (by number or length too), remove duplicate and blank lines, join lines, add prefixes, suffixes or numbering, and Alt+drag selects and types in a column. Convert has Base64, URL, HTML entities, Unicode and hex; JSON, XML, HTML, CSS, JS and SQL formatting and minifying; full and half width, hidden characters copied from web pages or AI chats, hashes and a word count.
For web pages, HTML, Markdown, CSS and JavaScript preview as you type, at phone or tablet width, with a console for the page's messages and errors. "Check the page" finds unclosed tags, repeated ids, missing alt text, and the title, description, viewport and canonical tags search engines need; the clean-ups strip the extra markup Word leaves behind. Files are opened and saved in your browser and never uploaded; unsaved work stays in this browser for next time.
How to use Online Text Editor
- 1Open or start
Drop files into the window, press Ctrl+O, or type in a new tab. Encodings and line endings are recognised.
- 2Edit and process
Use find and replace, line tools, conversions and the HTML tools in the side panel. Everything can be undone.
- 3Preview and compare
Preview pages as you type with a console, and compare line by line with another tab or the last saved version.
- 4Save
Press Ctrl+S, choosing the encoding and line endings. Chrome and Edge on a computer can write back to the original file.
Why use Cubfile for this
- Tabs and encodings
Several files at once; open and save UTF-8, GBK, GB18030, Big5, Shift_JIS and UTF-16, and reopen garbled text in another encoding.
- Regex find and replace
Match case, whole word, regex, in selection, \n \t escapes; $1 groups and \U upper case; see the changes first; search every tab.
- Lines and columns
Sort, remove duplicates and blank lines, join, add prefixes, suffixes and numbers; Alt+drag box selection and number columns.
- Live HTML preview
Phone and tablet widths with a console; a page check for tags and SEO; Word clean-up; to Markdown or plain text.
- Convert and format
Base64, URL, entities, Unicode, hex; JSON, XML, HTML, CSS, JS and SQL formatting and minifying; hashes, timestamps, word count.
- Bookmarks, compare, outline
Copy, cut or delete bookmarked lines at once; compare two texts line by line; jump through headings and functions.