How We Use Credit Cards

We require an active, valid credit card on file for most accounts. This is primarily a means to prevent abuse and ensure that we can collect payment at the end of the month.

Preauthorization Requests

We may send a preauthorization request to the issuing bank to verify a bank will authorize charges. Some credit card companies present these as real charges, which may surprise you.

A preauth is really just a hold on a credit card. We'll typically preauthorize a small amount (usually less than $5) after signup, then cancel the authorization immediately. Banks may show the preauth for up to 7 days, even though we have not collected any money.

When Will I Get Charged?

If you provision services beyond the free included usage, we will charge you actual money at the end of each month.

The prices of provisioned services are mostly fixed. If you provision a VM or Machine and leave it running all month, we'll charge you a predictable amount for that machine. It's difficult to accumulate charges unintentionally.

We'll happily refund you if you do create compute resources by mistake, just send an email to

There are some services that we meter based on external traffic (like outbound bandwidth). In theory, if you suffer an attack or an unexpected spike in traffic, these charges can add up.

We'll happily refund you if your app receives unexpected traffic and generates a surprisingly large bill. Just send an email to