Sendblue Sandboxes vs Shardflux

Sendblue Sandboxes costs $0.165 per vCPU-hour and Shardflux costs $0.04 per vCPU-hour. Sendblue Sandboxes runs containers. Shardflux runs Firecracker microVMs and offers GPUs.

Updated Oct 15, 2026

Sendblue Sandboxes

Isolated cloud Linux machines that AI agents control over an HTTP API.

Isolation: Container
Free tier: $100 free compute, once per phone number
Max session: Not listed

Visit site Sendblue Sandboxes profile

Shardflux

Serverless VMs for cloud agents that park when idle and keep their state.

Isolation: Firecracker microVM
Free tier: 30-day Pro trial, no card needed
Max session: Not listed

Visit site Shardflux profile

What is different

8 fields differ. The rest are the same or not listed.

Field

Sendblue Sandboxes

Shardflux

vCPU, per hour: Sendblue Sandboxes: $0.165; Shardflux: $0.04
RAM, per GiB-hour: Sendblue Sandboxes: Included; Shardflux: $0.015
Free tier: Sendblue Sandboxes: $100 free compute, once per phone number; Shardflux: 30-day Pro trial, no card needed
Billing: Sendblue Sandboxes: Bundled machine time; Shardflux: Active CPU time only
Largest sandbox: Sendblue Sandboxes: 2 vCPU · 8 GiB; Shardflux: 32 vCPU · 64 GiB
Concurrent sandboxes: Sendblue Sandboxes: Up to 5; Shardflux: Up to 200
Isolation: Sendblue Sandboxes: Container; Shardflux: Firecracker microVM
Pause and resume: Sendblue Sandboxes: No; Shardflux:

Full comparison

18 fields, at each provider's list price

Sendblue Sandboxessendblue.com/sandboxessendblue.com

Shardfluxshardflux.dev/#pricingshardflux.dev

Pricing

vCPU, per hour: Sendblue Sandboxes: $0.165; Shardflux: $0.04
RAM, per GiB-hour: Sendblue Sandboxes: Included; Shardflux: $0.015
Storage: Sendblue Sandboxes: Not listed; Shardflux: Retained storage is a monthly allowance per plan. No hourly storage rate is published.
Free tier: Sendblue Sandboxes: $100 free compute, once per phone number; Shardflux: 30-day Pro trial, no card needed
Paid plan from: Sendblue Sandboxes: Not listed; Shardflux: $9 / month
Billing: Sendblue Sandboxes: Bundled machine time; Shardflux: Active CPU time only

Limits

Max session: Sendblue Sandboxes: Not listed; Shardflux: Not listed
Idle stop: Sendblue Sandboxes: After 10 minutes; Shardflux: Not listed
Largest sandbox: Sendblue Sandboxes: 2 vCPU · 8 GiB; Shardflux: 32 vCPU · 64 GiB
Concurrent sandboxes: Sendblue Sandboxes: Up to 5; Shardflux: Up to 200

Platform

Isolation: Sendblue Sandboxes: Container; Shardflux: Firecracker microVM
GPU: Sendblue Sandboxes: Not listed; Shardflux:
Snapshots: Sendblue Sandboxes: Not listed; Shardflux:
Pause and resume: Sendblue Sandboxes: No; Shardflux:

Developer

SDKs: Sendblue Sandboxes: Not listed; Shardflux: TypeScript, Python
Integrations: Sendblue Sandboxes: Not listed; Shardflux: Claude Code, MCP

Trust

License: Sendblue Sandboxes: Not listed; Shardflux: Not listed
BYOC: Sendblue Sandboxes: Not listed; Shardflux: Not listed

Hourly cost

One sandbox running for one hour

Size

Sendblue Sandboxes

Shardflux

1 vCPU · 2 GiB: Sendblue Sandboxes: $0.165; Shardflux: $0.070
2 vCPU · 4 GiB: Sendblue Sandboxes: $0.330; Shardflux: $0.140
4 vCPU · 8 GiB: Sendblue Sandboxes: $0.660; Shardflux: $0.280

Compute only, at list rates.

Open the calculator

Which one fits

Based on the fields above

Shardflux fits when

You need GPUs.
You want each sandbox in its own microVM.
You use Claude Code or MCP.
You want the lower list price: $0.140 against $0.330 an hour for 2 vCPU and 4 GiB.

More comparisons

See all comparisons

Sendblue Sandboxes

Shardflux

What is different

Full comparison

Pricing

Limits

Platform

Developer

Trust

Hourly cost

Which one fits

Shardflux fits when

More comparisons

Related

Compare

Pricing

Browse