# Bounce rate explained | Propel

Source: https://runpropel.com/glossary/bounce-rate

Glossary

# What is bounce rate?

In email, the bounce rate is the share of messages that could not be delivered, usually because the address does not exist. A high bounce rate tells mail providers a sender is guessing addresses, and they start sending its mail to junk.

## What is the difference between hard and soft bounces?

A hard bounce means the address is wrong or gone, and it will never work. A soft bounce is a passing problem, such as a full inbox or a server that is down for a while. Hard bounces are the ones that hurt a sender's name.

## How do you keep it low?

- Check addresses before the first send.
- Never send to an address that has bounced before.
- Be wary of old lists: people change jobs, and their work addresses close.

A website's bounce rate, the share of visits that leave after one page, is a different number with the same name.

## What does Propel do?

An address that bounced is never written to again, from any campaign. Propel keeps the bounce and opt-out trend for each mailbox and each sending domain, so a rise shows early. See [Get customers](https://runpropel.com/get-customers).

Where Propel does this

[Get customers →](https://runpropel.com/get-customers)

Related terms

- [SPF, DKIM and DMARC](https://runpropel.com/glossary/spf-dkim-dmarc)
- [Do-not-contact list](https://runpropel.com/glossary/do-not-contact-list)
- [Cold-email warm-up](https://runpropel.com/glossary/cold-email-warm-up)
- [All terms](https://runpropel.com/glossary)