Modal

Modal is a Python-first serverless compute platform. The product that matters for this catalog is the Sandbox API: define an image, create a sandbox, then exec untrusted agent commands inside it. The same account also runs functions, cron, notebooks, and GPUs.

This page used to lead with a $355M Series C, $4.65B valuation, ~$300M ARR, and "1B+ sandboxes" as verified facts first-party metrics.

Key Features

• Sandbox API: Sandbox.create(.) then sb.exec(.). Docs also describe filesystem and memory snapshots.
• Compute as code: modal.App, images, functions, and sandboxes live in Python.
• Scale to zero: Idle compute is billed at $0. Workspace storage is not free. The pricing page lists $0.000347 / GiB-month for workspace storage.
• GPU menu: Live price table includes T4, L4, A10, L40S, A100-40GB, A100-80GB, H100, H200, B200, and a $0.049 / s B300. Confirm the SKU before you quote a GPU.
• Not the only agent sandbox: Compare E2B if you want Firecracker microVMs instead of Modal's isolation story.

Use Cases

• Agent tool loops that need a container and maybe a GPU in the same bill.
• Teams already running Modal functions who do not want a second sandbox vendor.
• Burst jobs that should drop to zero between runs.

Limitation: Modal is managed SaaS. The docs we used do not offer self-host or BYOC. Isolation is Modal's container/sandbox stack, not E2B's Firecracker guest kernel. Do not call gVisor or "1B sandboxes" a current first-party claim unless you re-verify it.

Pricing

Seat and compute from modal.com/pricing on 2026-08-17. Compute rates below are on-demand / reserved.

Selected on-demand compute (reserved is cheaper on the same page):

Getting Started

1. Read the sandbox guide.
2. pip install modal and authenticate.
3. Create an image, then Sandbox.create and exec.
4. Attach a GPU only after you have read the live SKU price.

Frequently Asked Questions

Is Modal only a sandbox?

No. Sandboxes sit next to functions, cron, and GPU jobs on the same platform.

Can I self-host it?

Not from the pages we used. Treat it as SaaS.

Are the old $250 Team and $30 free-credit numbers still right?

Yes, on the 2026-08-17 pricing page. The rest of the old writeup (valuation, ARR, 1B sandboxes) is not repeated here.

Alternatives

• E2B: Firecracker microVMs purpose-built for agent exec.
• Cloudflare Computer: Edge isolates if you are already on Cloudflare.
• OpenAI Agents SDK: Agent runtime. Use Modal under it if you need the sandbox.

Tips

1. Model CPU, memory, GPU, and storage as four meters. Seats are a fifth.
2. Confirm reserved vs on-demand before you screenshot a GPU hour.
3. Do not keep a sandbox warm "just in case". Scale to zero is the point.

Conclusion

Modal is still the Python serverless box with a first-class sandbox and a public GPU price list. Start at the sandbox guide and the pricing page, then compare E2B if you need a microVM instead of a Modal container.