Celesto vs Blaxel

Celesto vs Blaxel: both run agents in microVM-class sandboxes with desktop and CDP browser images, but Celesto costs 81% less per active hour on the same CPU and memory and includes a 20 GB+ disk, while Blaxel suspends idle sandboxes within seconds, resumes them in about 25 ms with memory intact, and stops charging for compute while they wait.

Pick by how busy the sandbox is: sandboxes that work steadily for long stretches favor Celesto's lower hourly price; bursty agents that sit idle between calls favor Blaxel's standby.

Same 1 vCPU · 2 GB sandbox, active: $0.015 vs $0.083; Per running hour. 81% or more less on every matched size.
Idle sandboxes: Stop to save; Celesto bills until you stop a sandbox. Blaxel moves idle sandboxes to standby on its own and bills only storage.
Disk included: 20–100 GB; In Celesto's price. Blaxel's writable filesystem uses memory; volumes cost $0.12 per GB-month.

Start with $5 free Read the quickstart

A 20 GB+ disk and an internet off switch, included.

A dot marks whoever has the edge on that line.

CelestoBlaxel

Isolation and access

Isolation model: Its own KVM virtual machine and kernel; microVM per sandbox (Firecracker, per its blog)
Start and resume: Under 2 seconds; Resume in about 25 ms from standby(Blaxel has the edge)
Shell access: Browser terminal, or celesto computer ssh with no SSH keys; Console terminal and bl connect; no native SSH
Docker inside: Supported; With the docker-in-sandbox image

Browser and desktop

Desktop view: Live desktop on the browser templates, read-only or with control; XFCE with noVNC image
Browser over CDP: Built-in Chromium at a CDP URL; Chromium image with CDP through a proxy

State and storage

Idle sandboxes: Billed until you stop them; stop keeps the disk; Standby after seconds idle, memory and processes kept, no compute charge(Blaxel has the edge)
Disk: 20 to 100 GB by size, included(Celesto has the edge); Writable layer in memory; one volume at $0.12 per GB-month
Lifetime: Persistent; stopped disks kept 30 days; 7 days on Tier 0, 30 days on Tier 1, unlimited from Tier 2

Network and tools

Egress control: Internet on or off (TypeScript SDK); Domain allow and deny lists (public preview); no single off switch
Public preview URLs: Up to 4 public HTTPS ports per sandbox; Public or private URLs, custom domains(Blaxel has the edge)
MCP: Hosted MCP server that creates sandboxes and runs commands; MCP server in each sandbox and a hosted management MCP
SDKs and API: Python, TypeScript, CLI, and a REST API; Python, TypeScript, Go, CLI, and a REST API

Price and limits

2 vCPU · 4 GB, per active hour: $0.030(Celesto has the edge); $0.166
Free start: $5 one-time credit, no card; Up to $200 in credits(Blaxel has the edge)
Running at once: Up to 10; 10 on Tier 0, more with larger top-ups

Celesto has the edge Blaxel has the edge

81% less per hour on every matched size.

Each Celesto size next to the same CPU and memory on Blaxel, or its nearest size, per hour.

Running-hour sandbox prices in USD, matched by CPU and memory
Hardware	Blaxel	Celesto
1 vCPU · 2 GB	$0.083/hour	$0.015/hourMicro, 20 GB disk included
2 vCPU · 4 GB	$0.166/hour	$0.030/hourStandard, 30 GB disk included
2 vCPU · 8 GB	$0.331/hourNearest size: 8 GB with 4 vCPU	$0.040/hourMemory, 40 GB disk included
4 vCPU · 16 GB	$0.662/hourNearest size: 16 GB with 6 to 8 vCPU	$0.080/hourLarge, 60 GB disk included
8 vCPU · 32 GB	$1.325/hourNearest size: 32 GBSelf-serve memory limit not published	$0.160/hourXL, 100 GB disk included

Blaxel bills memory only, at $0.0414 per GB-hour while active; CPU follows memory, so rows show the CPU Blaxel pairs with that memory. Standby is not charged for compute. Celesto prices include the root disk and apply while the sandbox runs.

Agents that work steadily, with big disks, cost less on Celesto.

Choose Celesto if

Sandboxes work steadily and 81% less per active hour adds up
The agent needs a real disk of 20 GB or more without a separate volume
You want an internet off switch for untrusted code
You want a 2 vCPU sandbox with 8 GB of memory, or 4 vCPU with 16 GB, priced by CPU and memory

Choose Blaxel if

Agents sit idle between bursts and should cost nothing while they wait
Sandboxes must resume in milliseconds with memory and processes intact
You need domain allow and deny lists or custom preview domains
You want a Go SDK

Questions.

Is Celesto cheaper than Blaxel?

Per active hour, yes. Blaxel charges $0.0000115 per GB of memory per second, $0.0414 per GB-hour, with CPU included, so 1 vCPU and 2 GB costs $0.083 an hour while active. Celesto Micro costs $0.015 an hour with a 20 GB disk, at least 81% less on every matched size. Blaxel stops charging for compute when a sandbox goes to standby, so an agent that is idle most of the time can cost less there.

Does Celesto have standby like Blaxel?

No. Celesto bills a sandbox while it runs; stop it and runtime charges end, with the disk, packages, and CelestoFS workspace kept for 30 days, but running processes end. Blaxel puts idle sandboxes into standby automatically, keeps memory and processes, and resumes in about 25 ms.

Can my agent use a browser in Celesto or Blaxel?

Both. Celesto's browser-agent template returns a CDP URL from computer.browser() and shows a live desktop view. Blaxel offers Chromium with CDP through a proxy, Playwright images, and an XFCE desktop over noVNC as sandbox images.

How much disk does each sandbox get?

Each Celesto size includes a root disk of 20 to 100 GB that survives stops, plus a CelestoFS workspace. Blaxel's writable filesystem lives in memory and uses about half of the sandbox's RAM; for more, attach one volume at creation, billed at $0.12 per GB-month.

What is a good Blaxel alternative for AI agents?

Celesto is a Blaxel alternative for agents that work steadily: each sandbox is its own virtual machine with a terminal, desktop view, CDP browser, public preview URLs, Docker, and a 20 to 100 GB disk that survives stops, from $0.015 per hour. New accounts get a one-time $5 credit with no card.

Start with $5 in credits. No card required.

Start with $5 free Read the quickstart

Blaxel details from its public pricing and documentation, as of October 17, 2026: Pricing · Sandboxes · Templates · Proxy and domains · Create sandbox API · Isolation. Celesto details come from the current sandbox catalog and feature list. Prices are list rates, not measured performance. Blaxel is a trademark of its owner; Celesto is not affiliated with it.