Email Bounce Rate Calculator.

A hard bounce is a permanent failure and a soft bounce a temporary one. In mail server replies, a status starting with 5 means the failure is not likely to be resolved by resending, and a status starting with 4 means sending later may succeed (RFC 3463). Remove hard-bounced addresses for good; soft bounces may go through later.

Mailbox providers such as Gmail, Yahoo and Outlook publish no bounce rate limit. Sending platforms set their own account rules. Amazon SES asks senders to keep bounces below 2%, reviews accounts at 5% and may pause sending at 10%, counting hard bounces only. The rule that applies to you is your own sending platform's.

Delivery rate is emails sent minus bounces, divided by emails sent. It means the receiving server accepted the email, not that it reached the inbox: email filed in spam still counts as delivered. Finding out where email lands takes an inbox placement test, not a calculation from your counts.

Mostly addresses that do not exist: old lists, typos, guessed address formats and people who have left a company. Full mailboxes and receiving servers that are down cause soft bounces. A receiving server refusing your email on policy grounds is about your sending rather than the address, and should not be treated as the address bouncing.

It should not count against the address. A 5.7 status means the receiving server will not accept email from you, for example over authentication or reputation, and the address itself may be fine. SendCanyon does not count 5.7 refusals or full mailboxes as bounces, so contacts are not suppressed because of a problem with your own sending.

When the sending platform decides the condition is not temporary. There is no standard rule, and platforms choose their own number of repeated soft bounces before they stop sending to an address. Soft bounces from the same address over several weeks usually mean the mailbox has been abandoned.

Verify addresses before you send, remove every hard bounce at once and for good, and do not send to addresses guessed from a name pattern without checking them. Check each import on its own, because one bad source can carry most of a campaign's bounces. SendCanyon checks contacts on import and holds risky ones back.