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Why do my app's emails go to spam? Gmail's rules in 30 seconds

Ship ItChecked against the official source

Source checked 30 Sept 2026 · Published 1 Oct 2026 · Last reviewed 1 Oct 2026 · By Ctrl+Z Therapy (how we test)

The short answer

Gmail asks every sender to set up SPF or DKIM on the domain the email comes from. Send more than 5,000 emails a day to Gmail, and you need SPF, DKIM and DMARC, plus one-click unsubscribe on marketing emails, and a spam complaint rate below 0.3%.

What to do

  1. Send from your own domain.
  2. Add the DNS records your email provider gives you.
  3. Send a test to a Gmail address, open Show original, and check that SPF and DKIM pass.

Source

Checked on 30 Sept 2026. Prices, limits and settings change, so check the source before you rely on them.

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