Click on the "MicroVMs" tab of the pricing page: https://aws.amazon.com/lambda/pricing/

Thanks! These tabs render badly on mobile, but you can click on “Functions” to hide it and then click the “MicroVMs” tab to show it.

This pricing model looks very complicated and unfriendly for hobbyists. Maybe it’s cheaper than exe.dev’s $20/month, but I have no idea. I’d have to a complicated calculation based on guesses to tell.

I don't think it's that complicated, but yeah, it's not as simple as $X/month.

The primary difference is that with Lambda you pay by the second, not by the month. According to my math, the break-even point for a 8GB allocation (the minimum exe.dev supplies) would be about 1.65 days of continuous runtime. Less than that, and you're better off with Lambda. More than that, and you're better off with exe.dev (assuming we're just talking about money and not opportunity cost). Lambda allows you to use just 2GB of memory, though, so being more memory efficient would change the break-even point to 6.61 days.

I’m running a web server in a VM and I use it every day. It’s mostly idle, but it’s continually available. I wonder how much “continuous runtime” that is?

The stopwatch starts when a request arrives and stops after your processor sends the response. You’re not charged for idle time. For low-demand services, it’s a bargain. The tradeoff is a bit of extra latency for cold starts (i.e. when a request hasn’t been processed in a while). Nowhere near a full classic VM launch though—typically under a second.