CapabilitiesSizes and regions
Resize while running
Change CPU or memory without stopping the machine or losing what is running.
Short answer: 1 of 16 providers offer it fully: Tensorlake. With a catch: Agent 37, Blaxel, Daytona, InstaBox, Morph and Runtime. Checked 29 October 2026.
Who offers it
Part of Sizes, regions and hardware, which explains why it matters.
Fully: Tensorlake. With a catch: Agent 37, Blaxel, Daytona, InstaBox, Morph and Runtime. Not at all: Boat, boxd, Cloudflare Sandbox, E2B, Lizard, Modal, Sandboxer, Sprites and Vercel Sandbox.
Memory can only shrink back to about what the running programs are using.
docs-confirmed “A sandbox can change its CPU, memory, and root disk allocation while it runs.” Source
The catch: You can change the size without stopping the machine, but it may move to another host and everything running in memory is lost.
docs-confirmed “start and resize answer 202 instead of 200 when they moved the instance to another host” Source
The catch: You can change the memory, but the sandbox resets, so anything running is lost.
docs-confirmed “Updates a sandbox's configuration. Note that certain changes (like image or memory) may reset the sandbox state.” Source
The catch: You can add cores and memory while it runs, but you cannot shrink them, and the feature has to be switched on by support first.
docs-confirmed “On a running sandbox, you can increase CPU and memory without interruption.” Source
The catch: Cores and memory change only while the machine is stopped, and take effect at its next start; the free plan cannot resize at all.
docs-confirmed “A paid machine moves to another size of its plan while stopped” Source
The catch: Disk space can grow while the machine runs, but changing cores or memory means restarting it.
docs-confirmed “CPU and memory changes still require reboot.” Source
The catch: You can change the memory only while the machine is paused, not while it is working.
docs-confirmed “resize this one while it is paused” Source
Note: Changing the size means stopping the machine and starting it again.
docs-confirmed “To change the size, stop the sandbox, then resume it with --type.” Source
Note: A size change reboots the machine, so running programs are lost.
docs-confirmed “A running machine reboots to apply it, so its disk persists and running processes are lost.” Source
Note: The size is fixed when the sandbox is deployed; changing it means deploying again.
Inferred from the instance type being set at deploy time.
inferred “Maximum vCPU” Source
Note: The machine keeps the size it was created with; there is no resize.
Inferred: no resize call appears in the docs or API reference.
inferred “Max vCPUs” Source
Note: The size is chosen when the sandbox is created and cannot be changed.
Inferred: the size list is closed and no resize is documented.
inferred “Sandbox sizes run from Small (2 vCPU / 4 GB) to Large (8 vCPU / 16 GB)” Source
Note: Resources are fixed when the sandbox is created; changing them means starting a new one.
Inferred: no resize method is documented.
inferred “Sandboxes have the same disk limits as other Modal containers” Source
Note: There is no way to change a running machine's size; you create a new one and copy your files across.
docs-confirmed “Moving to a smaller size isn't supported yet. To go smaller, create a new sandbox of that size and copy your files across” Source
Note: The shape is fixed, so there is nothing to resize.
docs-confirmed “The vCPU count and the storage ceiling are fixed” Source
Note: The size is set when the sandbox is created and cannot be changed during its life.
Inferred: no resize in the SDK reference.
inferred “Each vCPU includes 2 GB of memory.” Source
Related
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