About DiffNexa
DiffNexa compares two versions of a document or a web page and shows exactly what changed — with the wording and location behind each change as evidence, so you can check every result yourself.
What DiffNexa is
DiffNexa is a set of comparison tools that share one comparison approach and one results workspace:
- Files you compare. Upload an original and a revised PDF, Word document or Excel workbook, and DiffNexa lists every change between them.
- Web pages you check. Save a baseline of a public web page today, check the page again whenever you choose, and DiffNexa shows what is different now.
- An optional explanation step. After any comparison, AI Change Analyst can explain the changes that were found. It never decides what changed.
Why it exists
Documents and web pages are revised constantly: a contract comes back with edits, a supplier updates its terms, a price list is reissued, a spreadsheet is passed around and returned. Finding what actually changed usually means reading two long versions side by side, and the change that matters — one date, one figure, one sentence in a cancellation clause — is easy to miss.
General-purpose text comparison helps, but it tends to bury real changes in noise. A paragraph that moved to the next page looks rewritten. A new page number looks like an edit. A figure that went from 627 to 654 is shown as one number deleted and another added, and you work out the difference yourself.
DiffNexa exists to answer one question well: what changed? It reports each change the way a careful reader would describe it — “Vacancies changed from 627 to 654 (+27)” — sets aside differences that are not changes, and shows where each change is.
Know What Changed: how DiffNexa works
The comparison is deterministic
Every change is found by fixed, tested comparison rules, not by an AI model. The same two versions always give the same result. New comparison behaviour is checked against a library of document and page pairs whose correct results are known, so an improvement in one place cannot quietly make results worse in another.
Every change comes with evidence
Each change names where it is — a page, a heading, a sheet and cell, a section of a web page — and quotes the wording involved from each version it appears in. You never have to take a result on trust.
Differences that are not changes are set aside
Page breaks, line wrapping, page numbers, reflowed paragraphs, a web page's menus, cookie notices and timestamps are not reported as changes. When something is set aside as probably unimportant, DiffNexa says so and why, rather than hiding it.
Numbers and dates are compared as values
A changed amount is one change with the difference worked out; a moved deadline is one change with the number of days between.
AI is optional, and comes second
AI Change Analyst explains changes after the comparison has found them. It runs only when you ask, every statement it makes must point to a change DiffNexa found, and statements that cannot be matched to the evidence are not shown. The comparison and its evidence remain the source of truth.
As little as possible is kept
There are no accounts. Files are discarded when the comparison is done, results live only in your browser, and a web page's baseline is a file you keep. The Privacy Policy sets this out in full.
The tools
Compare two files
Upload an original and a revised version. Both are compared, then discarded — never stored.
- PDF Compare
Compare two PDF versions and see changes in text, numbers, dates and pages.
- DOCX Compare
Compare two Word documents and find changes in text, numbers, dates, lists and tables.
- Excel Compare
Compare two Excel workbooks and find changed cells, formulas, rows, columns, sheets and links.
Check a web page against your baseline
Save a copy of a public page as it reads today, keep the file, and compare the live page with it whenever you choose.
- Website Change Detector
Compare a public web page against a baseline you saved and see exactly what changed.
- Policy & Terms Monitor
Compare a privacy policy or terms page against a baseline you saved, and see which part of the document changed.
- Competitor Monitor
Compare a competitor’s public page against your saved baseline and see what changed.
- Price Monitor
Compare a public pricing or product page against your saved baseline and see what changed.
Optional, after any comparison
Explains the changes a comparison found, labels how significant each looks, and cites the evidence behind every statement. Available in all seven tools.
What DiffNexa does not do
Saying plainly what a tool cannot do is part of making its results trustworthy. Today, DiffNexa:
- does not read text inside images, including scanned PDF pages — it flags them instead;
- does not compare images, charts or visual layout;
- does not watch web pages for you — there is no scheduled checking and there are no alerts; you check when you choose;
- cannot read web pages behind a login, or pages that build their content in the browser with JavaScript;
- does not judge whether a change is good or bad for you, and does not give legal or financial advice;
- cannot promise to find every change in every file. It shows the evidence so you can check, and important results should be verified against the original documents.
Each tool's page lists exactly what it compares and what it does not.
Get in touch
Questions, bug reports and suggestions are welcome at info@diffnexa.com. The contact page lists what to include so we can help quickly.