Site Spy
Web change monitor in Developer tools
Watch a chosen part of any page and get diffs, history or RSS with little setup; handles JavaScript pages well. Critics want credit for its open-source base.
Watch a chosen part of any page and get diffs, history or RSS with little setup; handles JavaScript pages well. Critics want credit for its open-source base.
26 people gave an opinion
- recommend it
- 25
- criticize it
- 1
- approval share
- 96%
Recommended in 1 of 13 months
- November 2025: not recommended
- December 2025: not recommended
- January 2026: not recommended
- February 2026: not recommended
- March 2026: recommended
- April 2026: not recommended
- May 2026: not recommended
- June 2026: not recommended
- July 2026: not recommended
- August 2026: not recommended
- September 2026: not recommended
- October 2026: not recommended
- November 2026: not recommended (month in progress)
Why it doesn’t carry the badge
- 25 people recommend itNeeds 10 or more, met.
- 25 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 1 of 13 monthsNeeds 4 or more, not met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Follows changes via diffs and RSS
“click the exact part of the page you care about, and then follow changes as diffs, history, or RSS with very little setup”
Comment from 11 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS” “making it easy to pick the exact part of a page you care about and then inspect the change via diffs”
Comment from 11 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS” “pick the exact part of a page visually, then follow changes through diffs, history, RSS, and alerts”
Comment from 11 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS” - Comment from 12 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS”
- Comment from 12 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS”
- Comment from 12 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS”
Pick exact page part visually
“click the exact part of the page you care about, and then follow changes as diffs, history, or RSS with very little setup”
Comment from 11 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS” “making it easy to pick the exact part of a page you care about and then inspect the change via diffs”
Comment from 11 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS” “pick the exact part of a page visually, then follow changes through diffs, history, RSS, and alerts”
Comment from 11 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS” - Comment from 12 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS”
Useful for tracking granular updates
“This is cool. I'd use it to track when state wildlife agencies update their regulation pages”
Comment from 11 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS” “Great for opponent monitoring on political campaigns.”
Comment from 12 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS” “Super useful for people tracking granular updates!”
Comment from 12 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS”
What people warn about
Each mark is one comment
Light/dark mode toggle freezes
“toggling between light/dark mode results in a multi-second freeze”
Comment from 11 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS” RSS output hard to find
“I can't actually find the RSS output”
Comment from 12 Mar 2026 in “Show HN: Site Spy – Track webpage changes with diffs, element picking, and RSS”
What people said
24 of the 31 comments that mention it, newest first. Each links to the original comment.
“The real win is how it breaks down fixes step-by-step”
“The element picker + RSS output is exactly the right interface for that”
“RSS is underrated for this honestly.”
“the error flagging is a nice touch”
“I can't actually find the RSS output”
“I think its in poor taste to not attribute the opensource tool that the service is built on”
“cool idea, congrats on the launch”
“Super useful for people tracking granular updates!”
“Kudos for the choice of RSS!”
“Great for opponent monitoring on political campaigns.”
“pretty much exactly what the MCP server is designed for”
“toggling between light/dark mode results in a multi-second freeze”
“It's been around for a while and recommended by many.”
“This is cool. I'd use it to track when state wildlife agencies update their regulation pages”
“This is quite a lovely implementation.”
“Site Spy uses a real browser flow, so it generally handles JS-rendered pages much better than simple HTML-only polling tools”
“I have wanted this for so long!”
“this seems to be a very good execution of the concept”
“pick the exact part of a page visually, then follow changes through diffs, history, RSS, and alerts”
“this can be self hosted and it is for free”
“click the exact part of the page you care about, and then follow changes as diffs, history, or RSS with very little setup”
“making it easy to pick the exact part of a page you care about and then inspect the change via diffs”
“Cool stuff. You should make it OSS and ask a one time fee for it.”
“This is interesting, gonna try it on our next project!”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.