Old live URL vs new live URL. Missing pages, quiet nav drops, title and meta that shouldn't have changed, redirects that only exist on one side — one report, ranked by how much it will hurt if it ships.
Both sides are live sites. This is the shape a migration or redesign actually has — not baseline-vs-rerun visual regression.
| status | path | viewport | diff % | text ± | http a/b | notes |
|---|---|---|---|---|---|---|
| error | /careers | desktop | 200 / 404 | missing on B | ||
| layout | /pricing | desktop | 18.40% | 12 · meta 2 | 200 / 200 | page is 420px taller |
| diff | / | mobile | 6.12% | 4 | 200 / 200 | |
| diff | /about | desktop | 1.03% | 200 / 301 | redirect: /about-us | |
| text | /terms | desktop | 9 · meta 1 | 200 / 200 | copy changed, pixels didn't | |
| match | /contact | desktop | 200 / 200 |
Rows sort worst-first. Click any one for a slider, side-by-side, the raw pixel diff, or the text diff. HTTP and redirect mismatches get their own table. This mock is the shape of the HTML report the CLI writes — a named public teardown will live here once the first one is published.
Pixel percentages miss a nav item that vanished and a title that quietly changed.
Every page's rendered text is diffed GitHub-style, next to title, description, canonical,
og:*, headings, and links.
| tag | A | B |
|---|---|---|
| title | Pricing — Old Co | Plans — New Co |
| canonical | empty | https://new.example/plans |
| links | - Enterprise → /enterprise + Teams → /teams | |
MIT-licensed CLI. Point it at two hosts, get the HTML report, JSON, and an optional PDF of the worst visual diffs. Flags and mapping live in the repo.
I run the compare, read every finding, and send a written report a PM can act on: what broke, what went missing, what changed that shouldn't have, ranked by launch risk.
You send two live URLs and the section (or small site) that matters before launch. I run sidediff, read the output, and send back a ranked written report — not a zip of screenshots.
Whole-site migrations are a separate pass. Send the two hosts and I'll price it after a look at the sitemap — no list price on this page until there is a sample from a real job.
Sitemap plus a link crawl, so a stale sitemap does not decide coverage. One-sided 404s and redirects are findings, not dropped rows.
Migrations rename paths. Pair /products/foo with /shop/foo instead of comparing two 404s.
Layout-taller is not “changed.” Text-only changes get their own bucket. The report sorts worst-first so a PM can work the list, not a screenshot dump.
# clone, then bun install bunx playwright install chromium # flags, or no flags for the wizard (writes sidediff.toml, then runs) bun run compare --a https://old.example --b https://new.example --pdf
Report: sidediff-out/index.html, report.json, and with
--pdf a shareable report.pdf. URL mapping, logged-in capture,
hide/mask, viewports: bun run compare --help or the
README.
Yes. MIT-licensed. Clone it and run it whenever you want. The €249 is for the human pass: reading every finding and writing a ranked report against a launch date.
A ranked written report covering one section or a smaller site (about 40 URLs), desktop and mobile, plus the HTML report the CLI already produces. Turnaround is about 48 hours once both URLs are reachable.
Two live URLs (old and new), the section or paths that matter, and the launch date. Redirect maps help if the URL structure changed.
Send the two hosts. I'll look at the sitemap and quote a full-site pass. That price is not listed here until there is a real sample from a delivered job.
Agencies and delivery leads about to ship a migration or redesign — the people who eat week-2 escalations. Developers who want the CLI can skip the paid block entirely.