Running different types of VMs simultaneously on the free tier depends on the cloud provider you are using:
- AWS EC2 Free Tier: You can run multiple instances simultaneously as long as your total usage does not exceed 750 hours per month. However, instances with more than one vCPU are not eligible for the free tier. You can run multiple t2.micro or t3.micro instances (depending on the region) at the same time, but you must ensure that your total usage stays within the 750-hour limit. For example, you could run two instances for about 375 hours each per month[1][5].
- Azure Free Account: With Azure, you get 750 hours of free usage for both Linux and Windows virtual machines each month for the first year. You can run multiple VMs of the same type (e.g., two Linux VMs) as long as their combined usage does not exceed the 750-hour limit for that operating system. You can also run a Linux and a Windows VM simultaneously, each for up to 750 hours[2][3].
- Oracle Cloud Infrastructure (OCI) Always Free: OCI allows you to run up to two Always Free VM instances using the VM.Standard.E2.1.Micro shape. These instances can be of different types, but they must be within the Always Free limits and created in your home region[7].
- VMware Player: While VMware Player allows running multiple VMs simultaneously, it does not have a built-in feature for managing multiple VMs in a single window. You need to open a separate instance of VMware Player for each VM you want to run[4].
In summary, you can run different types of VMs simultaneously on the free tier with some providers, but there are specific limitations and requirements depending on the provider and the type of VMs you are using.
Citations:
[1] https://repost.aws/questions/QUqjIE9b9mSfOzVF75RqbqCQ/unable-to-run-simultaneously-two-ec2-instances-as-free-tier
[2] https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/create-free-services
[3] https://learn.microsoft.com/en-us/answers/questions/2180776/getting-two-linux-vms-in-always-free-instead-of-on
[4] https://askubuntu.com/questions/362158/is-it-possible-to-run-multiple-vmware-guests-using-free-vmware-player
[5] https://www.reddit.com/r/aws/comments/11snrr8/how_to_create_more_than_one_ec2_instance_free_tier/
[6] https://superuser.com/questions/589265/can-i-run-multiple-virtual-machines-at-once
[7] https://docs.oracle.com/iaas/Content/FreeTier/freetier_topic-Always_Free_Resources.htm
[8] https://www.reddit.com/r/homelab/comments/19e232t/how_many_vms_can_you_squeeze_out_of_a_4_core/
[9] https://stackoverflow.com/questions/19042025/amazon-ec2-free-tier-how-many-instances-can-i-run