Daytona vs Fly Sprites: pricing, isolation and limits

Daytona bills allocated vCPUs and memory and defaults to containers; Sprites are Firecracker microVMs billed on CPU used and memory in use.

Runtime runs the same job for 77% less than Daytona and 81% less than Sprites. 1,000 one-minute runs of a 2 vCPU, 4 GiB sandbox cost $2.76 on Daytona, $3.31 on Sprites with all 4 GB in use, and $0.64 on Runtime. Runtime measures CPU like Sprites, at about a third of the rate, reserves memory at under half of Daytona's rate, and puts every sandbox in its own microVM. Rates checked 23 September 2026.

At a glance

	Daytona	Fly Sprites	Runtime
Isolation	Containers by default; VM sandboxes as a separate class	Firecracker microVM	Firecracker microVM, own kernel, every sandbox
CPU	$0.0504 per allocated vCPU-hour	$0.07 per CPU-hour of measured CPU	$0.025 per vCPU-hour of measured CPU, with a small floor
Memory	$0.0162 per allocated GiB-hour	$0.04375 per GB-hour of memory in use	$0.0075 per reserved GiB-hour
Disk	First 5 GiB free, then $0.000108 per GiB-hour, stopped or not	100 GB; $0.50 per GB-month hot, $0.02 cold	Included while running; paused storage $0.08 per GB-month
Size	vCPUs, memory and disk chosen per sandbox	Memory managed by Fly	vCPUs and memory chosen per sandbox
Plan fee	None published	None required; optional monthly plans	None; prepaid credit from $10
Free start	$200 of compute, no card	$30 of trial credit	50 sandbox hours, no card
When idle	Stops after 15 idle minutes by default	Pauses itself; memory kept at first, the disk kept always	Pause keeps files, memory and processes, 1 to 365 days
Also offers	GPU sandboxes and Windows machines	SDKs in Go and Elixir as well as JavaScript and Python	Forks, desktop, code interpreter, MCP server

Is Daytona cheaper than Sprites?

It depends on how much memory the sandbox really uses. The two bill in opposite ways. Daytona charges for what the sandbox is given, every vCPU and every GiB, for as long as it runs. Sprites charge for what it uses: CPU time at $0.07 an hour, and memory in use at $0.04375 per GB-hour.

For the job below, an agent that keeps its CPU busy a third of the time, the Sprite's CPU costs $0.39 and the rest is memory. That puts the break-even at about 3.25 GB in use:

Memory the Sprite uses	Sprites	Daytona (4 GiB allocated)
1 GB	$1.12	$2.76
2 GB	$1.85	$2.76
4 GB	$3.31	$2.76

Busy CPUs move it the other way. With both CPUs working the whole minute a Sprite's CPU charge rises to $2.33, while Daytona's stays the same.

Runtime is cheaper than both at every row: $0.64 for the job, because its measured CPU is $0.025 a vCPU-hour and its memory $0.0075 a GiB-hour.

Cost for the same job

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 mostly waits for a model. The Sprite is assumed to use all 4 GB for the whole minute.

TextDaytona  CPU    1,000 × 60 s / 3,600 × 2 × $0.0504  = $1.68         Memory 1,000 × 60 s / 3,600 × 4 × $0.0162  = $1.08         Total                                         $2.76Sprites  CPU    1,000 × 20 s / 3,600 × $0.07        = $0.39         Memory 1,000 × 60 s / 3,600 × 4 × $0.04375 = $2.92         Total                                         $3.31Runtime  CPU    1,000 × 20 s / 3,600 × $0.025       = $0.14         Memory 1,000 × 60 s / 3,600 × 4 × $0.0075  = $0.50         Total                                         $0.64

At 100,000 runs a month that is $276.00 on Daytona, $330.56 on Sprites and $63.89 on Runtime. With both CPUs busy for the whole minute, it is $1.33 on Runtime against $2.76 on Daytona and $5.25 on Sprites, so Runtime is cheaper however busy the sandbox is. Plan fees, disk, network and free credits are left out.

What does an idle sandbox keep, and cost?

A Daytona sandbox stops after 15 idle minutes by default. Its disk past the first 5 GiB is billed at $0.000108 per GiB-hour whether it runs or not, and only VM sandboxes pause with their memory. A Sprite pauses itself shortly after its last activity, keeps its disk, and keeps its memory until it goes cold; cold storage is $0.02 per GB-month.

A paused Runtime sandbox keeps its files, memory and running processes for the retention you set, 1 to 365 days, for $0.08 per GB-month, and the next request wakes it:

TypeScriptimport { Sandbox } from "withruntime";const sbx = await Sandbox.create({ timeoutSeconds: 600 });await sbx.exec("echo state > /workspace/state.txt");await sbx.pause(); // memory and files are kept; compute billing stops// ... later, even from another process:const again = await Sandbox.connect(sbx.id);await again.wake({ timeoutSeconds: 1200 });await again.extend(600); // more time before the lease endsawait again.stop();

Which one to pick

• Pick Daytona for GPU or Windows sandboxes, sizes you set yourself, or $200 of free compute to start.
• Pick Sprites for sandboxes that use little memory and sleep for long stretches, a 100 GB disk, or SDKs in Go and Elixir.
• Pick Runtime for under a quarter of either price on an agent that waits, a microVM on every sandbox, and memory kept across a pause for as long as you choose.

Switch from either one

From Daytona, Runtime's SDK runs your code after one import change:

TypeScriptimport { Daytona } from "withruntime/daytona"; // was: from "@daytona/sdk"

Pythonfrom withruntime.daytona import Daytona  # was: from daytona import Daytona

Its stop() pauses a sandbox with its files and memory, and start() carries on.

From Sprites, client.createSprite(name) becomes Sandbox.create(), a Sprite found by name becomes Sandbox.getOrCreate(name), and sprite.execFile(cmd, args) becomes exec([cmd, ...args]):

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();}

Or give your coding agent the one instruction in migration: it switches the project on a branch, tests it on the free trial and reports the monthly saving. npx withruntime switch --from fly (or --from daytona) before your first top-up matches that top-up with credit, up to $100. The full side-by-sides are Runtime vs Daytona and Runtime vs Fly.io; how to pause and resume a sandbox covers idle sandboxes on Runtime.

Sources

Daytona and Fly.io pricing pages rechecked 25 September 2026; the rest checked 23 September 2026.

• Daytona pricing, Daytona sandboxes
• Fly.io pricing, Sprites, Sprites lifecycle and persistence
• Runtime pricing

Facts on this page were checked on 25 September 2026.