Pricing pages change. Treat this as a decision frame with dated links, not a frozen quote sheet.
Compare jobs before you compare invoices
GTmetrix plans are priced around diagnostic and monitoring features on their product model. Apogee Watcher plans are priced around organisations, sites, and scheduled PSI-based monitoring for agency portfolios. A cheaper line item that cannot separate clients or discover URLs is not cheaper once someone burns half a day rebuilding lists.
Portfolio maths to run yourself
Pick 5, 10, and 20 sites. For each tool, open the public pricing page and note which tier fits that site count, whether organisations/roles exist, and what reporting is included. Add the internal time you currently spend on manual runs. The useful comparison is total cost of the operating model, not the lowest monthly badge.
Public pricing references (verify before purchase): GTmetrix pricing · Apogee Watcher pricing. Framework dated 13 Nov 2026. Re-check vendor pages; do not treat any third-party figure here as a live quote.
When GTmetrix remains the rational spend
One or two sites, heavy need for real-browser location testing, and no client Viewer seats on the roadmap. Buy the diagnostic tool that matches that work. Add Watcher when the portfolio and retainer shape demand schedules and tenancy.