Version comparison · in your browser
Drop in the previous version and the new one. Each chapter shows up side by side, with every word that came in, went out or moved. The file never leaves your computer.
Nothing is uploaded · Nothing to install · .docx .odt .pdf .txt .md
+13 words−9 words4 edited paragraphs1 chapter moved
I · Down the Rabbit-Hole
2 edits
Alice was getting tired of sitting with her sister on the bank, and of having nothing to do.
Alice was beginning to get very tired of sitting by her sister on the bank, and of having nothing to do.
Then a white rabbit with pink eyes ran past her.
Suddenly a White Rabbit with pink eyes ran close by her.
III · A Caucus-Race and a Long Tale moved: in the previous version it was chapter II.
How it works
The previous one on one side, the new one on the other. They can be in different formats: yesterday's Word file against the PDF that went to the printer.
Using the headings you already set in the document. With no headings at all, the text is split into parts of similar length.
Unchanged text stays collapsed. Jump from change to change with N and P, chapter by chapter, to the end.
The king died. died in winter.
Features
A book, a paper or a contract isn't read in loose lines: it has chapters, paragraphs and sentences, and that's how the difference shows up.
Change a comma, and the word it belongs to lights up. The rest of the paragraph stays quiet, so you read the sentence instead of hunting for the change inside it.
Whole paragraph marked
She opened the window and the cold came in uninvited. She opened the window, and the cold came in uninvited.
Here
She opened the window window, and the cold came in uninvited.
The book is split at the chapters you already marked: the heading style in Word and LibreOffice, the # in Markdown, or CHAPTER 1 written in the text itself. A chapter that changed position shows up as moved, not as deleted and rewritten.
Curly quotes, dashes and ellipses swapped by autocorrect don't count as differences. Neither do bold, italics, font or margins: only the text is compared.
Previous version
"No" – she said... and left.
New version
“No” — she said… and left.
No difference
Word, LibreOffice, PDF, plain text and Markdown, in any combination. In PDFs, headers, footers and page numbers are dropped, and words hyphenated at the end of a line become whole again.
Fourteen color themes, each in light and dark, five fonts and six text sizes. The default is Ink, the e-reader gray, which leaves color only for what changed.
Every version of the manuscript saved on its own, in your browser, so you can go back to any point and compare any two. It's what comes after the comparison tool.
Privacy
The manuscript is read and compared inside your browser. There's no server that receives the file, so there's nothing to leak, sell or train anyone on.
The comparison runs in your browser, in the background, without freezing the page. Not a single byte of the file crosses the network.
Both versions stay in your browser's storage, so you can reload the page without dropping everything in again. Clearing the site's data erases them.
No ad pixels, no third-party scripts, not even the fonts come from elsewhere. Nobody sees what you compare.
Pricing
Everything unlocked for 7 days, so you can compare the whole book before deciding. Like it, pay once.
US$0 for 7 days
Everything the license has, no card needed.
US$12 once
For anyone revising the book down to the last version.
Everything in the trial, plus:
Don't need the trial? Get the license now
FAQ
For anyone who needs to know what changed between two versions of a text. The writer between drafts, or with the file that came back from the publisher. The researcher with the paper revised after peer review. The lawyer with the draft contract that came back from the other side. The editor who needs to show what they touched, and the student with the thesis their advisor returned.
No. The file is read and compared inside your browser, on your computer. Both versions are kept only in the browser's storage, so you can reload the page without dropping them in again.
Verso is a JavaScript program that runs entirely in your browser. When you drop a file, the page reads it through the File API and hands it to a Web Worker, a thread of the browser itself. There the engine opens the file (.docx and .odt are ZIP packages with XML inside; a PDF is read by Mozilla's pdf.js, also in the browser), splits chapters and paragraphs and works out the differences: first between paragraphs, then word by word within each one. None of these steps touches the network.
The server only handles your account: the Google sign-in and the license. It has no address that accepts a file. Both versions are kept in IndexedDB, your browser's database, so you can reload the page without dropping them in again. The page also declares a Content-Security-Policy with connect-src 'self': the browser refuses any connection from it to another domain, and no third-party script loads.
You don't have to take our word for it. There are three ways to check:
-method:GET in the filter, which leaves only the requests able to carry data. Drop the files, PDFs included, and wait for the comparison: the list stays empty. Without the filter, you only see downloads of code and fonts from verso.mtnhome.app itself.Word (.docx), LibreOffice (.odt), PDF, plain text (.txt) and Markdown (.md), in any combination. A PDF doesn't store paragraphs, only letters with a position on the page, so there the comparison is a reconstruction: in a 99-page book, 895 of the 900 paragraphs came back whole. When you can, use the editor's file.
It needs Word open, mixes text changes with formatting changes and shows everything in a single document, with old and new text interleaved. Here the versions sit side by side, chapter by chapter, and only the text counts.
First by the document's headings: the Heading 1 style in Word and LibreOffice, or the # in Markdown. Without those, by PROLOGUE, CHAPTER 1, PART 2 or EPILOGUE written in the text. Without any of that, as is usual with PDFs, the book is split into parts of similar length.
It shows up as moved, not as deleted on one side and written on the other. The same goes for a paragraph that changed position within a chapter.
Yes. In our tests, a 250-page book is read and compared in about a tenth of a second.
No. It's a web page: it opens in your computer's browser, and the file never leaves it.
You use everything for 7 days, no card needed. If you want to keep going, you pay US$12 once, by card. It's not a subscription, and nothing renews on its own.
Free for 7 days · Nothing to install · Works with the file you already have
Compare nowThe file never leaves your computer.