Modal is an AI infrastructure platform, made by Modal, that runs code in the cloud without servers for the customer to manage, a model called serverless computing. Its documentation lists four main uses: low-latency inference of AI models, batch jobs that run massively in parallel, training and fine-tuning of models on GPUs, and Sandboxes, isolated environments that execute code written by AI agents.
A developer installs the modal Python package and marks ordinary Python functions with decorators that declare the container image and the GPU type, so all configuration is code, with no YAML files. Modal puts the code in a container, runs it in the cloud, and adds containers automatically when traffic grows; it pools capacity from all major clouds. A function can also become an HTTPS endpoint or run on a schedule. Python is the main language; JavaScript, TypeScript and Go can call Modal Functions.
Modal is a hosted service billed per second of CPU, GPU and memory use, with no charge for idle resources. The Starter plan has no monthly fee and includes free credit each month; the Team plan adds a monthly fee.