See when your Gmail messages get opened. Sign in with Google — or connect your own Supabase backend.
Users
16
+15 in 30 days
Rating
5.0 / 5
+5.00 in 30 days
Ratings
2
+2 in 30 days
Store rank
#166K
#138K among extensions
Version
1.0.6
updated 17 Oct 2026
Users
monthly, 1 months
Latest, 18 Oct 2026:16 usersMove the mouse over the chart for any month
Ratings count
monthly, 1 months
Latest, 18 Oct 2026:2 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About Free Email Tracker for Gmail — Read Receipts & Open Tracking | Kilroy
Kilroy is an email tracker for Gmail, built to be honest.
It shows you when the messages you send have been opened: a quiet double-check and a count appear on the sent message itself, and a dashboard rolls up opens over time and by recipient. Link clicks can be tracked too, if you want the stronger signal.
Where most trackers overstate what they know, Kilroy is careful. An open is an image being fetched, not proof a person read your message — so it sets aside security scanners, Apple Mail's privacy prefetch, and your own re-reads, and it never guesses a location from a proxy. The first-open time is the figure you can actually rely on.
Your data stays yours. Tracking is kept in an account only you can read, and one click lets you point Kilroy at your own database instead. Because it's open source, every claim here can be checked against the code.
A few things worth knowing:
• Tracking is a switch beside Send — turn it off for any single message.
• Nothing is added to your email: no signature, no branding.
• No credit card and no separate password — sign in with Google and you're set.
Open source: github.com/RelayLabs-apps/kilroy
Learn more: kilroy.relaylabs.site
Growth
Window
Users
Change
Ratings
Rating
7 days
+3
+23.1%
0
0.00
30 days
+15
+1500.0%
+2
+5.00
Chrome Web Store search rankings
Where Free Email Tracker for Gmail — Read Receipts & Open Tracking | Kilroy appears when people search the store, with the 30 day change