Website change monitoring: see exactly what changed between scans
BYDIFF automatically monitors website and competitor changes across pages, SEO metadata, content, links, images, forms, code, robots.txt and Sitemaps. Version history preserves evidence and Compare shows the exact difference between scans.
For: business owners, SEO specialists, developers and web agencies that need factual control over changes on their own and competitor websites.
Start with the overview. Then inspect the exact difference.
After a scan, BYDIFF shows website health, scan history and changes between saved versions in one interface.
After the trial, plan and payment are available in your dashboard. After 1,000 URLs Scanner Agent asks for confirmation before continuing a large scan.
Configurable retention plus protected ★ checkpoints.
Appearance, content and metadata; desktop, tablet and phone.
What does DIFF mean?
The BYDIFF name reflects the product’s core mechanism: comparing two website states.
DIFF is short for Difference. BYDIFF saves website states during scans, compares them, and shows what was added, removed, or changed. Recognized dynamic values such as view counters, dates, time, nonces and tokens do not count as meaningful changes by themselves.
Why BYDIFF is useful
Four practical workflows based on factual website changes.
Verify which pages, product cards, copy, prices, images and SEO elements actually changed between scans.
Compare SEO, developer and agency reports with the website's actual state.
Spot discovered new pages, categories, products, copy, images, links, public prices and SEO fields.
Catch 404/410, 5xx, missing URLs, unexpected metadata changes and other problems after releases and updates.
What the extension tracks
It is not limited to Title and copy. BYDIFF compares multiple page layers.
A comparison you can verify visually
Choose two saved versions of the same URL and inspect differences by layer.
Description: previous version
H1: Product catalog
Description: updated version
H1: New arrivals
Split mode shows both copies at the same time with synchronized scrolling. Visual archive presets include desktop 1440×900, tablet 768×1024 and phone 390×844. Archived JavaScript is not executed.
Automatic monitoring
Checks can run manually or on a schedule while Chrome is open.
The background queue avoids scanning multiple websites simultaneously and supports pauses between projects.
Changes, scan problems, HTTP 5xx, successful no-change scans and local-folder reminders.
Gentle, Balanced or Fast. BYDIFF automatically slows down on heavy pages and 429/503 responses.
State, queue, speed, retries, 429/503, current URL, stall time and safety caps.
Less dynamic noise
For dates, counters, online chats and other constantly changing blocks you can create CSS exclusions or URL masks. An exclusion does not modify the website or delete the archive; the matching change simply stops being treated as significant. Recognized view counters, typical dates and time, UUIDs, nonces, tokens and other dynamic values are also filtered from the change log.
Your first comparison in 4 steps
Enter the domain and optionally give the project a custom name.
HTML+CSS copies, images and visual history are stored in the BYDIFF data directory.
The first successful scan becomes the baseline.
The second successful scan already shows real changes.
BYDIFF FAQ
Short answers about the product, monitoring and history storage.
What is BYDIFF?
BYDIFF is a website and competitor change monitoring service. It saves page states and shows the exact difference between scans.
Who is BYDIFF for?
For business owners, SEO specialists, developers and web agencies that need factual control over website changes.
Where is change history stored?
Monitoring history for History and Compare is stored locally in a folder selected by the user.
What does BYDIFF track?
Pages, SEO metadata, content, links, images, forms, code, robots.txt, Sitemaps and technical states.