Best Email Tracking for Gmail in 2026

Outsolvi is the top pick because it runs natively on Gmail through a Chrome extension AND on Outlook (Desktop, Web, New Outlook) at full feature parity, exposes Tier 1 to 5 confidence scoring on opens, and includes AI features at the $7 yearly base tier. For Gmail-only teams running sequence-driven outbound at high volume, Mixmax is the premium alternative. For cheapest paid, Mailtrack Pro at $4.99 yearly.

The Outsolvi Gmail extension runs in Chrome and Chromium-based browsers (Edge, Brave, Arc). For organisations on Chrome Enterprise with strict extension policies, Outsolvi is also available as a Google Workspace add-in installable from the Workspace Marketplace, which works under stricter IT policies but has slightly less compose-pane UI than the Chrome extension.

Yes. Apple MPP affects any tracking pixel regardless of which mailbox provider hosts the email. A recipient on a Gmail-hosted mailbox reading through Apple Mail with MPP enabled produces the same MPP pre-fetch signature as a Microsoft 365 recipient reading through Apple Mail. Apple Mail has roughly 58 percent global email-client market share per Litmus in early 2026. Outsolvi grades these as Tier 4 with 18 percent confidence and excludes them from open counts. The detailed math is in the [open-rate accuracy piece](/blog/email-open-rate-accuracy).

Since December 2013, Gmail routes every embedded image through googleusercontent.com servers. Google's image-fetching bot loads the tracking pixel before the human opens the email, and the cached image can be re-fetched as the user scrolls, generating duplicate open events. Outsolvi applies a 3-minute dedup window on Gmail-proxy traffic and a stricter User-Agent pattern check, so a single human read does not get counted as multiple opens. Most tools do not apply this filter.

Chrome extension is the default and has the richer UI surface (custom compose-pane elements, sidebar integrations). Workspace add-in works under stricter IT policies (organisations that disallow third-party Chrome extensions) but has a more constrained UI surface. If your IT team allows Chrome extensions, pick the extension. If they do not, the Workspace add-in is the alternative.

Of the seven trackers on this list, only Outsolvi runs natively on Outlook. The other six are Gmail-only. If there is any chance your team adds Outlook users in the next 12-24 months, picking a Gmail-only tracker now means re-platforming later. Outsolvi removes that constraint by covering both clients from day one with one unified dashboard.