Morph vs Prime Sandboxes: branching or breadth for RL

Morph branches a running VM into many replicas; Prime runs many fresh microVMs. The 2 vCPU, 4 GB benchmark costs $1.67 on Morph and $1.52 on Prime.

Runtime costs 62% less than Morph and 58% less than Prime for rollouts that wait on a model. 1,000 one-minute runs of a 2 vCPU, 4 GiB sandbox with 20 CPU-seconds of work each are $1.67 on Morph, $1.52 on Prime Sandboxes and $0.64 on Runtime.

At a glance

	Morph	Prime Sandboxes	Runtime
Isolation	Full virtual machines	Hardware-virtualized microVM, own guest kernel	Firecracker microVM, own kernel
Price	$0.05 per MCU-hour: 1 vCPU, 4 GB or 16 GB of disk	$0.02 per vCPU-hour, $0.0125 per GiB-hour	Measured CPU and reserved memory
Branching	Infinibranch, to hundreds of replicas	Listed as coming soon	Forks, up to 10 running copies
At once	Set by plan	1,024 to start	100 paid, 50 in the first week
Plan	Free with no credit; Developer $40, Team $250 a month	None; rates through 22 December 2026	None; prepaid credit from $10

Two shapes of RL environment

A search-heavy agent that explores many paths from one state wants Morph's branching: set up once, copy the live machine hundreds of times. A rollout farm that runs thousands of independent episodes wants Prime's breadth. Runtime sits between: forks of a warmed-up sandbox, ten at a time, at the lowest price per run.

Cost for the same job

2 vCPU and 4 GB (2 MCUs on Morph), 60 seconds, 20 CPU-seconds, 1,000 runs, with Prime's 5 GiB disk:

TextMorph    Size   1,000 × 60 s / 3,600 × 2 MCU × $0.05          = $1.67Prime    CPU    1,000 × 60 s / 3,600 × 2 × $0.02              = $0.67         Memory 1,000 × 60 s / 3,600 × 4 × $0.0125            = $0.83         Disk   1,000 × 60 s / 3,600 × 5 × $0.0002            = $0.02         Total                                                  $1.52Runtime  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

With both CPUs busy for the whole minute, it costs $1.67 on Morph, $1.52 on Prime and $1.33 on Runtime.

Which one to pick

• Morph for tree search over one live machine.
• Prime Sandboxes for wide, independent rollouts.
• Runtime for the cheapest run and forks that exist today.

See Runtime vs Morph and Runtime vs Prime Sandboxes.

Sources

Morph rates checked 23 September 2026; Prime Sandboxes rates checked 25 September 2026.

• Morph Cloud pricing, Morph Devboxes
• Prime Sandboxes overview, Prime Sandboxes launch
• Runtime pricing

Facts on this page were checked on 25 September 2026.