Is serverless cheaper for your use case?

Have you ever needed to estimate the cost of building a new application using serverless tech? Maybe you simply needed to give stakeholders or clients a heads-up on what to expect to pay. Or maybe you did this to guide your decision on whether to use serverless over a more traditional server- or container-based stack.

If you did go down this route, you probably had to roll your own spreadsheet. This can get very complex very quickly whenever you have a distributed system with several services in the mix.

My friend Xavier Lefèvre has just published his AWS Serverless Cost Calculator which aims to solve this problem. Here are a few things I really like about it:

• Your inputs to the spreadsheet are in terms of business metrics (e.g. number of daily user sessions) rather than lower-level service metrics (e.g. number of function invocations).
• The calculator has sensible defaults for mapping these business metrics to the units that AWS actually bill for, but these defaults can be customised if you don’t agree with them.
• Almost all the commonly used services within the AWS serverless suite are catered for.
• In his announcement blog post, Xavier explains that in order to understand the Total Cost Of Ownership of a serverless solution you need to take into account much more than the cloud infrastructure costs (a horse that I will continue to flog!)

I strongly recommend you start by reading the blog post, but if you’re itching to jump straight to the calculator, go here and be sure to choose “Make a Copy” from the File menu to ensure you have edit access and can toggle between the different dropdown presets that Xavier has made available.

Here’s the article link again: Is serverless cheaper for your use case?

— Paul