Glossary
What is Event Match Quality (EMQ)?
Event Match Quality (EMQ) is a score from 0 to 10 that Meta shows in Events Manager for each event type received through the Conversions API. It estimates how effective the customer information attached to your server events is likely to be at matching those events to Meta accounts.
EMQ is driven by the quality and coverage of the identifiers in each event’s user_data: hashed email (em) and phone (ph), the fbc and fbp browser identifiers, a stable external_id, client IP address and user agent. More valid identifiers, correctly normalized and hashed, generally mean a higher score.
The score matters because matching is what turns an event into an attributed conversion. Events Meta cannot connect to an account cannot be credited to a campaign, or used for optimization and audience building. A low EMQ therefore usually shows up as underreported results and weaker delivery.
Improving EMQ is mostly a data-completeness exercise: send every identifier you legitimately have on every event, normalize before hashing (lowercased emails, phone numbers in E.164), and preserve fbc/fbp by capturing click IDs first-party. EMQ is Meta-specific; Google and TikTok report matching differently, but the underlying idea is the same: richer identifiers lead to better attribution.