Celesto vs Tenki
Celesto vs Tenki: both sell VM sandboxes for agents and GitHub Actions runners, but Celesto costs 81% less per running hour on the same CPU and memory and ships the desktop, CDP browser, and a 20 GB+ disk ready to use, while Tenki keeps memory across pause, filters egress by domain, and runs macOS CI.
Pick by what the agent needs: a ready browser, a large included disk, or a lower hourly price favors Celesto; memory snapshots, domain allow lists, or macOS runners favor Tenki.
- Same 2 vCPU · 4 GB sandbox
- $0.030 vs $0.166
- Per running hour. 81% or more less on every matched size.
- Browser and desktop
- Built in
- On Celesto's browser templates. Tenki documents installing Chrome, Xvfb, and noVNC yourself.
- Same 2 vCPU · 4 GB CI runner
- $0.0005 vs $0.004/min
- Linux x64 GitHub Actions runners, per minute.
Desktop, CDP browser, and a 20 GB+ disk ready on day one.
A dot marks whoever has the edge on that line.
Isolation and access
- Isolation model
- Its own KVM virtual machine and kernel
- A VM with its own kernel
- Cold boot
- Under 2 seconds
- Under a second, per its product page(Tenki has the edge)
- Shell access
- Browser terminal, or celesto computer ssh with no SSH keys
- SSH from the CLI, with port forwarding(Tenki has the edge)
- Docker inside
- Supported
- Supported
Browser and desktop
- Desktop view
- Live desktop on the browser templates, read-only or with control(Celesto has the edge)
- Install Xvfb, x11vnc, and noVNC yourself
- Browser over CDP
- Built-in Chromium at a CDP URL(Celesto has the edge)
- Install Chrome and expose CDP through a preview URL
State and storage
- Snapshot and resume
- Stop and start keep disk and packages; processes end
- Pause and snapshots keep memory and disk; fork from a snapshot(Tenki has the edge)
- Disk per sandbox
- 20 to 100 GB by size, included(Celesto has the edge)
- 5 GiB root disk by default, wiped on terminate
- Persistent workspace
- CelestoFS, not limited by disk size
- Volumes from 1 MiB to 50 GiB
Network and tools
- Egress control
- Internet on or off (TypeScript SDK)
- Off, or domain and CIDR allow lists once Tenki enables them(Tenki has the edge)
- Public preview URLs
- Up to 4 public HTTPS ports per sandbox
- 20 per plan, with a TTL
- MCP
- Hosted MCP server that creates sandboxes and runs commands
- Hosted MCP server; Claude Code is the supported client
- SDKs and API
- Python, TypeScript, CLI, and a REST API
- TypeScript, Python, Go, CLI, and a gRPC API
Price and limits
- 2 vCPU · 4 GB, per hour
- $0.030(Celesto has the edge)
- $0.166
- Largest sandbox without a plan fee
- 8 vCPU · 32 GB(Celesto has the edge)
- 4 vCPU · 8 GB; larger needs Team at $250 a month
- Free start
- $5 one-time credit, no card
- $100 one-time credit, half after adding a card(Tenki has the edge)
- Running at once
- Up to 10
- 5 on Starter, 100 on Team
GitHub Actions runners
- Linux x64, 2 vCPU · 4 GB
- $0.0005/min(Celesto has the edge)
- $0.004/min
- Platforms
- Linux x64, Ubuntu 24.04
- Linux x64 and macOS on Apple Silicon(Tenki has the edge)
- Caching
- actions/cache built in
- Actions cache, dependency mirrors, sticky disks (beta)(Tenki has the edge)
Celesto has the edge Tenki has the edge
81% less per hour on every matched size.
Each Celesto size next to the same CPU and memory on Tenki, or its nearest size, per hour.
| Hardware | Tenki | 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 | $0.230/hour | $0.040/hourMemory, 40 GB disk included |
| 4 vCPU · 16 GB | $0.461/hourTeam plan only, $250 a month | $0.080/hourLarge, 60 GB disk included |
| 8 vCPU · 32 GB | $0.922/hourTeam plan only, $250 a month | $0.160/hourXL, 100 GB disk included |
Tenki prices are its per-second vCPU and RAM rates multiplied out to an hour; its first 5 GiB of disk is free. Celesto prices include the root disk. Credits and plan fees are not applied. Matching CPU and memory does not imply equal performance.
Browser agents and Linux CI cost less on Celesto.
Choose Celesto if
- You want to pay 81% less per running hour for the same CPU and memory
- Your agent needs a desktop and CDP browser without building the image yourself
- Sandboxes need a 20 GB or larger disk that survives stops
- You need 8 vCPU or 32 GB without a $250 monthly plan
- Your Linux CI should cost less per minute
Choose Tenki if
- You need pause and snapshots that keep memory and running processes
- You need egress allow lists by domain or CIDR
- Your CI needs macOS runners or dependency mirrors
- Your team works over SSH with port forwarding
- You want a Go SDK
Questions.
Is Celesto cheaper than Tenki?
Yes, on list price. Tenki charges $0.000014 per vCPU-second and $0.0000045 per GiB-second, which is $0.166 an hour for 2 vCPU and 4 GiB. Celesto Standard has the same CPU and memory for $0.030 an hour with a 30 GB disk included, and Celesto is at least 81% less on every matched size. Tenki's Starter plan caps a sandbox at 4 cores and 8 GB; larger sandboxes need its $250 monthly Team plan.
Do Celesto and Tenki both run GitHub Actions?
Yes. Celesto CI runs Linux x64 jobs on Ubuntu 24.04 with actions/cache built in, at $0.0005 a minute for 2 vCPU and 4 GB. Tenki runs Linux x64 and macOS on Apple Silicon, with dependency mirrors, at $0.004 a minute for the same Linux size.
Can my agent use a browser in Celesto or Tenki?
Celesto's browser-agent template includes a Chromium browser your code drives over CDP by calling computer.browser(), and a live desktop view. Tenki documents a guide that installs Chrome, Xvfb, x11vnc, and noVNC in the sandbox and exposes CDP through a preview URL.
Does Celesto keep memory when a sandbox pauses, like Tenki?
No. Celesto keeps the disk, installed packages, and CelestoFS workspace across stop and start, for 30 days after a stop, but running processes end. Tenki's pause and snapshots keep memory and disk, and can fork new sessions from a snapshot.
Do Celesto and Tenki support MCP?
Both host an MCP server. Celesto's at https://mcp.celesto.ai/mcp lets Claude Code, Cursor, or any MCP client create sandboxes, run commands, and publish ports. Tenki's hosted MCP server lists Claude Code as its supported client today.
What is a good Tenki alternative for AI agents?
Celesto is a Tenki alternative when agents need a ready browser and a large disk: 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.
Tenki details from its public pricing and documentation, as of October 17, 2026: Pricing · Sandbox · Sessions · Concepts · Volumes · Chrome guide · Runners. Celesto details come from the current sandbox catalog and feature list. Prices are list rates, not measured performance. Tenki is a trademark of its owner; Celesto is not affiliated with it.