Email Bounce Rate: Formula, Benchmark, and How to Lower It
Email Bounce Rate
Email bounce rate is the percentage of sent emails that could not be delivered and were returned, calculated as bounced emails divided by total sent times one hundred.
The formula and what's good
Bounce rate = (bounces / sent) x 100. Keep it under 2%. Above that, mailbox providers read it as a poorly maintained list and start filtering you. A sudden spike usually means a stale list, unverified addresses, or a purchased list. Compute yours with the email bounce rate calculator.
Hard vs soft
A hard bounce is permanent (bad address) and must never be retried. A soft bounce is temporary (full mailbox) and can be retried a few times. The distinction drives how you handle each, and the soft bounce vs hard bounce email page breaks it down.
How Nitrosend handles bounces
Bounce rate is tracked per domain, and every send is gated on that domain's health, so a rising rate throttles sending before reputation burns. Hard bounces are suppressed automatically, so a dead address doesn't get mailed again by mistake.
Past the definition
Knowing the formula does not fix a rising bounce rate. An AI agent that suppresses hard bounces automatically and gates sending on domain health does. I built Nitrosend around that idea: describe the send, and the agent keeps bounce rate low without you tracking a dashboard number.
FAQ
What is email bounce rate?
The percentage of sent emails that couldn't be delivered and were returned, calculated as bounces divided by total sent times one hundred.
What is a good email bounce rate?
Under 2%. Higher rates signal a poorly maintained list to providers and start hurting deliverability.
What causes a high bounce rate?
A stale list, unverified addresses, or a purchased or scraped list full of dead addresses and spam traps.