Runtime vs Runloop

Runtime runs agent code in microVMs, like Runloop's devboxes, and costs 88% less for an agent that mostly waits on a model.

The saving: 1,000 one-minute runs of a 2 vCPU, 4 GiB sandbox cost $0.64 on Runtime and $5.33 on Runloop. At 100,000 runs a month that is $63.89 against $532.56, $469 a month saved.

Where Runtime is better

• You pay for the CPU you use. Runloop bills a devbox's CPUs and memory for as long as it runs. Runtime measures the CPU your code actually uses, so time spent waiting on a model costs only a small floor, a twentieth of a vCPU.
• Lower rates on every meter. $0.025 per vCPU-hour against Runloop's $0.108 per CPU-hour, and $0.0075 per GiB-hour of memory against $0.0252 per GB-hour. Even with both CPUs busy the whole time, the example job costs $1.33 on Runtime and $5.33 on Runloop.
• Pause keeps memory. A paused Runtime sandbox wakes with its processes still running, kept for 1 to 365 days. A suspended Runloop devbox keeps only its disk, and its processes must be restarted.
• Forks of a running sandbox. Copy a sandbox with its memory and running processes, and try several things from exactly that point.
• No plan fee. Runloop's Pro plan is $250 a month plus usage. Runtime is prepaid credit from $10, with 50 free sandbox hours to start.
• Your agent sets itself up. It runs npx withruntime sandbox run --trial -- ..., shows you a link, and starts once you approve in the browser. No API key goes into a prompt or a config file, and the MCP server reuses the same connection.

At a glance

Runloop's figures come from its public pricing and documentation, checked 23 September 2026.

	Runtime	Runloop
Isolation	Firecracker microVM, own kernel	microVM, with a container inside
CPU billing	$0.025 per vCPU-hour of measured CPU, with a small floor	$0.108 per CPU-hour while the devbox runs
Memory billing	$0.0075 per reserved GiB-hour	$0.0252 per GB-hour
Disk	Included while running	$0.00034236 per GB-hour
Plan fee	None; prepaid credit from $10	Basic free; Pro $250 a month plus usage
Free start	50 sandbox hours, no card	$50 of credit, no card
Suspend, resume	Pause keeps files, memory and processes	Suspend keeps the disk; processes restart

Cost for the same job

Take 1,000 runs of a 2 vCPU, 4 GiB sandbox. Each run lasts 60 seconds and keeps the CPU busy for 20 CPU-seconds: an agent that spends most of its time waiting for a model. On Runloop that is the MEDIUM devbox: 2 CPUs, 4 GB and 8 GB of disk.

TextRuntime  CPU    1,000 × 20 s / 3,600 × $0.025           = $0.14         Memory 1,000 × 60 s / 3,600 × 4 × $0.0075      = $0.50         Total                                             $0.64Runloop  CPU    1,000 × 60 s / 3,600 × 2 × $0.108       = $3.60         Memory 1,000 × 60 s / 3,600 × 4 × $0.0252      = $1.68         Disk   1,000 × 60 s / 3,600 × 8 × $0.00034236 = $0.05         Total                                             $5.33

• Saving: 88%, or $4.69 per 1,000 runs.
• Per month: at 100,000 runs, $63.89 on Runtime against $532.56 on Runloop.
• Busier work: with both CPUs busy for the whole minute, $1.33 on Runtime against $5.33 on Runloop.

Plan fees, storage while suspended, network, taxes and free credit are left out of both. See pricing for Runtime's terms.

How to switch

Give your coding agent the one instruction in migration. It replaces the Runloop calls on a branch, tests them on the free trial, and tells you what you save each month. Your old code stays on the main branch until you merge.

Runtime:

TypeScriptimport { Sandbox } from "withruntime";const box = await Sandbox.create({ funding: "trial" });try {  console.log((await box.exec("python3 -c 'print(6 * 7)'", { check: true })).stdout);} finally {  await box.stop();}

When Runloop may fit better

• Agent benchmarks. Runloop runs SWE-Bench and other public benchmarks, and builds custom ones from your data.
• Your own cloud and compliance. Runloop deploys into your cloud account and states SOC 2, HIPAA and GDPR readiness.

Sources

Checked 23 September 2026.

• Runloop pricing
• Devbox sizes
• Devbox lifecycle
• Runloop
• Runtime pricing, security and products