Two versions of anything, side by side, with every added, removed and altered line marked and the altered words picked out. Code, a config file, two drafts of a letter, two versions of a policy. The comparison is made in this tab and both texts stay in it; the diff sites that do this keep a copy of what you paste.
It compares lines, then words. Lines are matched with the same algorithm git uses. Inside a line that changed, the words that differ are marked, so a one-character edit in a long line is visible at once.
It knows nothing about what the text means. REDLINE reads a contract and knows what a clause is. This reads text and treats every line alike, which is exactly right for code, configuration, lists and drafts.
Big texts are fine; enormous ones are slow. A few thousand lines compare in a blink. Two files with tens of thousands of lines and few lines in common can take seconds, and the summary says how long it took.
The patch is a real unified diff. The download and the copy are the format git, patch and every code review tool read, so a change made here can be applied elsewhere.
Nothing leaves this tab. Both texts stay in the page. There is no history and no clipboard kept, and closing the tab is the end of it.
Not here. Use REDLINE for those; it reads .docx and PDF and shows what moved in a contract. DELTA is for text you can paste or open as a text file.
It treats any run of spaces or tabs as one space and ignores space at the ends of lines, so reformatted code or re-wrapped prose does not show as changed. 'Ignore capitals' does the same for case.
'Show only the changes' keeps two lines of context around each change and folds the rest, the way a code review does. Untick it to see every line of both texts.
No. Open the network tab in your browser's developer tools and paste anything you like; nothing goes out.