Runtime vs Northflank

Runtime is built for agent sandboxes and costs 42% less than Northflank 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 $1.11 on Northflank. At 100,000 runs a month that is $63.89 against $111.10, $47 a month saved.

Where Runtime is better

• You pay for the CPU you use. Northflank bills the vCPUs and memory a sandbox holds 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.
• Cheaper memory. $0.0075 per GiB-hour on Runtime against $0.00833 per GB-hour on Northflank, and a GiB is about 7% larger than a GB.
• A sandbox is one call. Sandbox.create() returns a running sandbox, with no service, project or deployment plan to set up. Northflank creates each sandbox as a service.
• Pause and fork keep memory. A paused Runtime sandbox wakes with its processes still running, kept for 1 to 365 days, and a fork copies a running sandbox with its memory.
• 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.
• Guardrails for agents. Give an agent a read-only key or a daily spending limit per key, and cap any create with maxCostMicros. Every write takes an idempotency key, so a lost response never creates a second sandbox.

At a glance

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

	Runtime	Northflank
Isolation	Firecracker microVM, own kernel	microVMs for CPU workloads, gVisor for GPU workloads
CPU billing	$0.025 per vCPU-hour of measured CPU, with a small floor	$0.01667 per allocated vCPU-hour
Memory billing	$0.0075 per reserved GiB-hour	$0.00833 per GB-hour
Plan fee	None; prepaid credit from $10	None published for compute
Free start	50 sandbox hours, no card	2 free services and 1 free database
Sandbox model	A sandbox, created in one call	A service with a deployment plan

Cost for the same job

Take 1,000 runs of a 2 vCPU, 4 GiB sandbox (4 GB on Northflank). 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.

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                                          $0.64Northflank  CPU    1,000 × 60 s / 3,600 × 2 × $0.01667  = $0.556            Memory 1,000 × 60 s / 3,600 × 4 × $0.00833  = $0.555            Total                                          $1.11

• Saving: 42%, or $0.47 per 1,000 runs.
• Per month: at 100,000 runs, $63.89 on Runtime against $111.10 on Northflank.
• Busier work: with both CPUs busy for the whole minute, $1.33 on Runtime against $1.11 on Northflank.

The more of its time an agent spends waiting, the more Runtime saves. Storage, network, taxes and free allowances 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 Northflank 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 Northflank may fit better

• Work that keeps every CPU busy. Northflank's allocated vCPU rate is lower than Runtime's measured rate, so a job that uses all its CPUs all the time costs less there: $1.11 against $1.33 in the example.
• GPUs. Northflank rents GPUs by the hour, including L4, A100 and H100.
• Your own cloud and many regions. Northflank runs in your AWS, GCP or Azure account as well as its own regions. Runtime runs in one US region.

Sources

Checked 23 September 2026.

• Northflank pricing
• Northflank sandboxes
• Sandboxes on Northflank
• Runtime pricing, security and products