Free web-based utility that compares and reports differences in plain text pasted into it. It has a novel text diff algorithm that detects when a paragraph or line has been moved up or down in a document. Most other text diff utilities do not have this feature - they inaccurately report moved lines as additions and deletions. Users have a choice between comparing whole lines against each other or switching to fine-grained word and character comparisons. There is an option to omit identical paragraphs or lines in its output unless they are near differences. Ability to navigate from one difference to the next. Also can move from one group of adjacent differences to the next group. The background color changes to alternately light blue and yellow to indicate sentence reordering within a paragraph
Good set of options. You can just see the diffs with a few lines of context either side. Plus unlike a lot of other online diff text tools this one allows you to change whether you compare at the level of lines, words or characters.
I've found it handles large documents much better than most of the other ones.
Cons
The 8 different layouts is a little confusing. Just pick the "Maximum size compare" or one of the "2 big..." ones.
good options, works well, compares plain text fine
tilda2013
Pros
Diff Text gives you the choice of having the results in a single pane (like WinDiff) or having the original text side-by-side with the modified text in two vertical panes.
It has navigation from one difference to another via arrows, but this is not needed. You can instruct the software to only display unaltered lines near the differences. You can see all the differences at once with a few lines either side as context.
You can go one step further and output the diff's with no context at all.
At the moment Text Diff is the only web compare utility I've found that uses https so that any text you compare is encrypted during transit.
I've compared a few of these utilities and this one actually works with huge amounts of text.
Conveniently any moved blocks that are found are colored grey or blue, rather than red or green (deletions and additions). So you easily know whether something has just been moved or is a real addition / deletion. A nice touch that the competition does not have.
Cons
It does one thing and one thing well i.e. compare plain text. It doesn't handle any other formats.
The website gives you a choice of seven different compare web-pages, each one with a slightly different arrangement of controls and result windows. It is a bit too much and they should have just stuck with three.
Summary
Good piece of software that works well and I will definitely bookmark this one. Has unique features.