Email Bounce Rate Calculator
Bounces divided by messages sent times 100, with a rating: under 1 percent is excellent, past 2 percent your sender reputation starts to suffer.
Bounce (%)
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Email bounce rate
Bounce rate tells you what share of the emails you sent never made it to the inbox: bounce rate = bounces / sent × 100%. Send 10,000 and have 200 bounce, and you're at 2.0%. A soft bounce is temporary, like a full mailbox, an out-of-office, or a server that's down. A hard bounce is permanent, like an invalid address or a domain that doesn't exist. Once you climb past roughly 3%, deliverability suffers, because Gmail and Outlook start docking your IP and domain reputation and routing the next sends to spam. A high bounce rate usually points to a dirty list: old leads, scraped addresses, no double opt-in. Pull hard bounces right away, and suppress soft bounces after a few failures in a row.
Applications
Cleaning and validating lists with NeverBounce, ZeroBounce, or Kickbox; keeping your ESP (Email Service Provider) reputation healthy on SendGrid, Amazon SES, Mailgun, and Postmark; getting SPF/DKIM/DMARC aligned; staying compliant with the U.S. CAN-SPAM Act and Brazil's LGPD; and running double opt-in so bots and typos never make it onto the list in the first place.
FAQ
Soft or hard bounce? A soft bounce is temporary and worth retrying; a hard bounce is permanent because the address is invalid. Most ESPs suppress hard bounces on their own and drop soft ones after N failures in a row.
What is an acceptable bounce rate? Under 2% is healthy. The 2–5% range is worth a closer look. Above 5%, the major providers see a red flag and may start throttling your IP.
How do I reduce bounce rate? Make double opt-in mandatory, clean the list on a regular schedule, never buy lists, and check addresses at signup with a real-time email-verification API.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.