Start with the two versions you want to check
A text comparison answers a practical question: what changed between this version and that version? Paste the earlier copy into Original text and the later copy into Revised text. Choose Characters or Lines, then select Compare. The result combines the two versions into a marked view, with labels for added and removed text while unchanged passages appear as ordinary text. It is a reading aid, not an editor that accepts or rejects changes for you.
Keep the direction consistent. Added means present in the revised version but not in the original at that position in the comparison. Removed means present in the original but absent from the revised version. Reversing the inputs reverses those meanings. If you are checking a correction from a colleague, the draft you sent normally belongs in the original field and the returned draft belongs in the revised field.
Use matching sections when a document is long. Comparing the introduction of one file with the conclusion of another may produce a valid result, but it does not help you review a revision. Include a little unchanged text before and after a suspected edit so you can recognize its context. Preserve a separate copy of your source documents, especially if you intend to make further edits after reviewing the result.
One field may be empty. Comparing an empty original with a revised passage marks the passage as added; putting the passage only in the original marks it as removed. With both fields empty there is nothing to compare. The tool works with the text you paste, not with the original document's fonts, comments, page layout or tracked-change history.
Choose characters for details and lines for structure
Character mode
Character comparison is useful when you need to locate a small edit inside a sentence. It can expose a changed digit, an extra space, a punctuation mark or a different letter. This is the default mode. Start here for short messages, headings, product labels or a paragraph where the two versions are mostly the same. Read the surrounding words as well as the highlight before deciding whether the edit is correct.
Line mode
Line comparison treats each line as a unit. If a line changes, you may see the old line removed and the new line added, even if only one word differs. That broader view is often easier for lists, short configuration excerpts and text in which each line represents a separate record. It helps answer which entries changed without spreading many small highlights across each entry.
A line is separated by an actual line break in the input. A long sentence wrapping visually onto another row on your phone does not become a second line for this purpose. Narrowing the screen can change the display without changing the comparison units. When you need to compare paragraphs separately, check whether the source really contains line breaks between them.
Neither mode is a word-by-word mode or a meaning-based review. Changing the mode changes the level of detail, not the underlying purpose. You can start with Lines to find the affected area, then compare that short area using Characters. This two-step approach is especially useful when a whole document contains several unrelated edits and the detailed result is difficult to scan.
Read additions and deletions together
On screen, added text has a plus label and removed text has a minus label, alongside their visual styling. Unchanged passages appear as ordinary text without a label. The copied report also includes an equals label for unchanged passages. A replacement usually appears as a removal near an addition. There is no separate claim that the removed words and added words have the same meaning. You decide whether they represent a correction, a rewrite or a new instruction.
For a compact character example, compare the original “Total: 15” with the revised “Total: 18”. The shared “Total: 1” remains unchanged, the final 5 is removed and the final 8 is added. This is helpful when checking a number that is easy to overlook in a longer paragraph. The tool identifies the textual difference; it does not establish which amount is factually correct.
For a line example, put “red” on the first line and “blue” on the second line of the original. In the revised input, keep “red” on the first line and put “green” on the second. In Lines mode, the first line remains unchanged while the second line is represented by the removed old entry and added new entry. The line break after the shared first entry is part of that shared text.
Repeated words or repeated lines can make an alignment less obvious. A comparison algorithm finds a way to represent the changes; it cannot know which copy of a repeated sentence a person moved while editing. If a passage moved, it can appear as removed in one place and added in another. Do not interpret those labels as proof that the writer deleted and retyped the passage rather than moving it.
Check spaces, punctuation and copied text
This page does not offer switches to ignore capitalization, spaces or punctuation. Those details are part of the comparison. “Code” and “code” are different text, as are a straight quote and a curly quote. A result showing a tiny change is not necessarily a false alarm: it may be a real difference that is simply hard to see at normal reading size.
Try the original “A B” and the revised “A B”, with two spaces in the revised version. Character mode identifies an added space. The result may look almost identical because spaces have no visible ink. Read the labels and inspect the source fields instead of assuming that a small blank highlight is meaningless. Tabs and line breaks can create similarly subtle differences.
Accented letters can also be represented by different underlying character sequences. A precomposed accented character and a letter followed by a combining accent may look alike while not being the same sequence. The tool is not a Unicode normalization service. If visually identical text still differs, consider how it was copied or produced before changing it simply to silence the comparison.
Pasting from a PDF can introduce hard line breaks, repeated headers or unusual spaces. Pasting from a formatted document can lose information that existed only in formatting. Review a short extract first and decide whether the pasted content matches what you intended to check. Do not remove all line breaks just to make the result quieter if those breaks separate records or important sections.
Work within the comparison limits
Each input accepts up to 12,000 characters according to the field counter. This is an input-size ceiling, not a promise that every pair below it can be compared. A pair of short but completely different texts can require more work than a longer pair with one small change. There is also a complexity guard to avoid spending too long constructing a very large set of edits.
If you receive a message about too many differences, try Lines mode or compare shorter corresponding sections. Split by a paragraph, heading or record boundary rather than cutting through a word. Keep a small amount of shared context in each pair. When comparing several sections, track which original section belongs to which revision so that no part is skipped or compared twice by accident.
The displayed counter uses the string length handled by the browser. Some emoji and combined characters occupy more than one unit, so a count is not always the number of symbols you see. The same distinction matters when a paste reaches the limit sooner than expected. Reduce the actual input rather than relying on the visible number of letters alone.
An error is not a partially successful report. Shorten the inputs or choose another mode and run the comparison again before copying anything. Editing either source field or changing the mode clears the previous result, which helps prevent an old report from being mistaken for the current comparison. This page is intended for bounded text excerpts, not large document archives or entire code repositories.
Copy the report without confusing it with the final text
Copy result copies a text report containing the addition, removal and unchanged labels. It does not copy a clean revised document with the removed passages silently discarded. This distinction matters when pasting into an email, a ticket or a shared note: the labels explain what changed, but they are not part of the text you ultimately want to publish.
For a final clean version, use the revised source after you have checked it. For a review record, use the marked report and explain which version was the original. If the receiving application strips colors or styling, the written labels still communicate the type of change. Avoid manually selecting only a colored fragment when a reviewer needs the nearby unchanged context to understand it.
After copying, paste into the destination and check the beginning, the changed area and the end. Some receiving applications wrap lines differently or treat pasted content as formatted text. That does not automatically mean the comparison changed. Keep the two source versions available until you have confirmed that the report communicates the intended edits.
An identical-text message means the supplied inputs match for this comparison. It does not verify an entire file you did not paste, nor does it check facts, spelling or document metadata. If both inputs were accidentally copied from the same version, the result can correctly say they are identical while your intended review remains unfinished.
Use the right tool for the next step
Comparing texts is different from detecting plagiarism, identifying AI writing or assessing whether two passages express the same idea. A paraphrase can change nearly every word while keeping the meaning. A single changed word such as “not” can reverse the meaning despite a very small textual difference. Read important passages in full and do not turn the size of a highlight into a quality or originality score.
This page also does not translate, correct grammar, merge revisions or inspect Word and PDF files directly. Extract the relevant plain text yourself, then compare it here. For code, the result shows characters and lines rather than whether the program still works. For instructions, it shows edits rather than whether the new procedure is safe or complete.
When the review reveals a term that needs changing throughout a draft, use Find and replace text, then compare the original with the result to review the scope of that change. When you only need capitalization changed, the uppercase and lowercase converter handles that separate action. Keeping those steps separate makes it easier to understand why the final text differs.