Around 0.5% is average, but it depends on the industry and audience. Use your own historical average as a reference. Keep an eye out for sudden spikes and act quickly. Take a good look at what you send. Are all sales hard, all the time? Is buy email database it marketing? Or is it useful content that the recipients of the email will find valuable? Put yourself in their place. Would you like to unsubscribe from your email? Deliver more content tailored to your subscribers' specific interests and behaviors.
Don't send too many messages to your audience. Too frequent emails are a good way to increase unsubscribes. Offer the buy email database option to receive less frequent emails on your subscribe (and unsubscribe) page. Give your audience a personalized preference center where they can update their information, manage their options, indicate the content they want to receive and choose how often messages are sent.
Ask people why they're quitting with a short survey so you can understand their reasons for quitting. Make sure this is an optional step buy email database during the unsubscribe process. Set expectations upfront about how often people will receive emails from you (daily, a weekly roundup, as items become available or go on sale). If you rarely send, make it clear. Ask them to whitelist you (add your email address to their contact list)