Renting Out Your Mac for AI Inference Using Darkbloom
You can now rent out your old M1 Mac to serve open source language models for $150 a month…
If you have an M-Series Mac that’s sitting idle most of the time, there is now a service called “darkbloom.dev” that lets you rent out this unused compute.
They do it in such a way that the individual computers on their network can never actually “see” what’s being processed, so users can run these models with data privacy.
This could be an interesting option going forward to mitigate the high cost of entry for running models locally.
Higher-end Macs tend to be quite expensive, but if you can earn back some money by renting them out whenever you aren’t using them, that could make the purchase more attractive.
What you actually earn depends heavily on utilization though, and right now darkbloom has more suppliers than buyers. Their estimate assumes your Mac is busy 60% of the time. When I checked, the network was running at 11%. So the real payout sits well below what they advertise…
I stumbled upon it when I saw this tweet:
Double checked and the darkbloom website confirms estimated earnings of $146 a month for that machine. For a newer M4 Pro with 64 GB RAM the calculator shows $217.
Interestingly the ROI seems to be favoring rather old models (M1, M2) with enough RAM. Their estimate scales with memory bandwidth, NOT with chip generation, and Apple’s Max and Ultra chips have had 400 to 800 GB/s since 2021. An M4 Pro does 273.
| Chip | Bandwidth | RAM | Estimate |
|---|---|---|---|
| M1, M2 Pro | 200 GB/s | 32 GB | $158 |
| M4 Pro | 273 GB/s | 64 GB | $217 |
| M1, M2, M3 Max | 400 GB/s | 64 GB | $310 |
| M4 Max | 546 GB/s | 64 GB | $417 |
| M1 Ultra | 800 GB/s | 64 GB | $602 |
So a 2021 M1 Max earns about $90 a month more than a 2024 M4 Pro.
I did find one review on it. They only ran it for a day and a half, and it did work. But the earnings landed at the very bottom of the range, almost all of it the base reward for staying online rather than anything from actual inference.
That review also turned up something the website doesn’t mention: you have to let darkbloom install device management (MDM) on your Mac.
It is the same thing corporate IT installs to monitor a machine and confirm it meets their security standards, and darkbloom needs it to back up the privacy guarantee - which is fair enough I guess.
That being said, not every machine in every context is eligible for that, and handing that much access to a new provider nobody has heard of yet is not something everyone will be comfortable with.