Check your internet speed — ping, download, upload. Free, no sign-up, no file to install.
Honest note: this test measures speed via public test servers (Cloudflare first, with a backup server if the first one fails). Each phase — ping, download, upload — runs independently with its own failover, one after another so the phases do not distort each other. Results depend on your connection, device and network load, so they are close to real speed, not lab-perfect. Works best in phone Chrome.