An often overlooked cost of using cloud services is data egress. This is the cost of sending data out of the cloud provider’s network to the public internet.
Here’s what 1 TB of egress beyond the free allowance would cost you with each provider:
Note: These pricing examples are based on several assumptions.
Your actual costs may differ. Always check the cloud provider’s website for the most up-to-date pricing.
Understanding cloud egress
If you’re a developer, chances are you’ve used cloud services for tasks like storing files, running your apps, or hosting websites.
These services are typically charged based on usage, but one of the costs you might not be aware of until you get your cloud bill is data egress.
It’s important to understand how it works because data egress fees can quickly add up, especially when you plan on moving a lot of data around.
Let’s break down what data egress is, how much it costs, and what you can do to keep your data egress costs down.
What is data egress?
Data egress is the term used to describe data leaving a network, more specifically, data leaving your cloud provider’s network out to the public internet. This can be data sent from a cloud provider to a user, or data sent from one cloud provider to another.
Cloud providers typically charge for egress based on the amount of data sent out of their network, and it’s usually measured in gigabytes (GB) or terabytes (TB) of data transfer per month.
Data egress vs ingress
From the cloud provider’s perspective, there are two types of data transfer:
- Ingress: data entering a network. Typically free.
- Egress: data leaving a network. Typically charged.
In practice, it might look like this:
- When a user uploads a file to a cloud storage service, that’s considered ingress to the cloud provider.
- When the user downloads the file, that’s considered egress from the cloud provider.
To download the file, the user’s device is requesting data from the cloud provider’s network, and the cloud provider is sending the data out to the user (or to an intermediary like a content delivery network). This is where egress fees come into play.
Why do cloud providers charge for egress?
Cloud providers charge for egress because it costs them money to send data out of their network. They have to pay for the infrastructure and bandwidth required to send data to users.
However, egress fees may also be used to discourage certain types of usage, such as moving large amounts of data across providers.
Most cloud providers do offer a certain amount of free egress each month. For example, as an account-wide allowance (eg. 100 GB / mo), or pooled across the number of servers you have with them (eg. 1 TB / mo per server).
So depending on your usage and the cloud provider you choose, you may not have to pay for egress at all.
Keeping egress costs down
Here are some factors to consider when trying to keep egress costs down:
- Content Delivery Network (CDN) Cache and serve static assets closer to your users. That way, you can reduce the amount of data transferred from your cloud provider to your users.
- Compression: Compress your data before sending it to reduce the amount of data transferred. Gzip and Brotli are popular compression algorithms.
- Data transfer pools: Consider using a cloud provider that offers a data transfer pool. This allows you to pool together the data transfer allowances of multiple services within the same account.
- Monitoring: Set up usage and billing alerts to notify you when you’re approaching your free allowance or a certain threshold.
- Private networking: Your cloud provider may offer free egress for data transferred between services within the same data center or region when using a private network. However, do watch out for NAT gateway charges and other fees that may apply.
Conclusion
Data egress is the cost of sending data out of a cloud provider’s network to the public internet. It’s important to understand how it works because data egress fees can quickly add up, especially if you’re moving a lot of data out of the cloud.
Tip: You can use this website to compare cloud providers and their egress costs to find which one is the best fit for your use case.
