Fly.io vs Vercel

Fly.io and Vercel target different deployment strategies for web applications. Fly.io operates as a container-native platform, pricing its instances from $1.94/mo to $131.80/mo, which provides developers with 0.256 GB up to 16 GB of RAM. Vercel focuses on a frontend-centric model, offering a free tier that scales to $20.00/mo, with memory constraints capped between 1 GB and 3 GB. While Fly.io grants more headroom for memory-intensive background processes, Vercel prioritizes high-volume traffic handling, bundling up to 1000 GB of egress compared to the fixed 100 GB limit on Fly.io.

• Fly.io charges $0.02/GB for egress overages, which is significantly cheaper than Vercel’s $0.15/GB penalty for exceeding bandwidth quotas.
• Both providers align on storage costs, charging $0.15/GB for additional persistent disk space beyond their respective base allocations.
• Vercel enforces a stricter RAM ceiling of 3 GB, whereas Fly.io allows scaling up to 16 GB, making the latter more suitable for stateful services or long-running worker processes that require beefier hardware.
• Fly.io includes up to 160 GB of disk storage in its upper tiers, providing more local capacity for containerized data than Vercel’s environment, which is not designed for heavy disk persistence.

Choosing between these platforms depends on your architecture. If your stack relies on heavy compute or background workers, Fly.io provides the necessary RAM and disk space, often running on Firecracker micro-VMs that compete with standard VPS performance. Vercel is better suited for teams managing static sites or edge-rendered applications where egress volume is the primary concern and the operational simplicity of a managed build pipeline outweighs the need for direct container control.