What Are OTUs?
When we tell someone that a project needs “2,000 GPU-hours,” it sounds precise. It isn’t. The OpenToken Unit (OTU) is a standardised measure that makes heterogeneous compute legible to innovators, donors, and partners.
The problem with GPU-hours
When we tell someone that a project needs “2,000 GPU-hours,” it sounds precise. It isn’t. A GPU-hour on an NVIDIA A100 is not the same as a GPU-hour on an RTX 4090. The A100 has more than three times the memory. The RTX 4090 has comparable raw processing speed but can handle a much narrower range of workloads. An hour on a V100 — a perfectly capable machine — delivers roughly a third of the useful work of either.
This matters because OpenToken aggregates compute from multiple sources. Our pilot draws capacity from commercial cloud providers, sustainable infrastructure partners, academic HPC facilities, and distributed GPU networks. The hardware is heterogeneous by design. That is how we keep costs low enough to offer free compute to innovators who could never afford hyperscale cloud pricing. But heterogeneity creates a communication problem. When a donor funds compute for a project, they deserve to know how much research (or, more broadly, how much ‘intelligence’) their contribution actually enables, regardless of which machine happens to execute it. When a researcher receives an allocation, they need to understand what they are getting. And when we report our impact, we need a unit that means something consistent.
Introducing the OpenToken Unit
The OpenToken Unit (OTU) is a standardised measure of AI compute. One OTU is defined as one hour of a single NVIDIA A100 80GB GPU. This particular GPU is the workhorse of the current AI research ecosystem, widely deployed across university computing centres and commercial providers alike.
Every other GPU type is converted into OTU equivalents using a fixed exchange rate. An hour on a more powerful machine is worth more than one OTU. An hour on a less powerful machine is worth less. The exchange rate captures both the processing speed and the memory capacity of the hardware, because for the workloads our innovators run, memory is often the binding constraint, not raw speed.
This is not a novel concept. The US National Science Foundation’s ACCESS programme uses a similar approach to allocate compute across dozens of heterogeneous national facilities. Grid computing federations have used token-based allocation models for decades. We are applying an established principle to a new context: making donated compute legible to a global community of innovators, donors, and partners.
Why this matters for donors and sponsors
If you contribute to a project on OpenToken, OTU tells you exactly what your contribution achieved.
Without OTU, we would have to say something like: “Your donation funded 1,200 hours on a mix of RTX 4090s and V100s across two providers.” That is technically accurate but practically meaningless. It gives you no sense of how much research you enabled or how your contribution compares to another donor’s.
With OTU, we can say: “Your donation delivered 600 OTUs to a project building a crop disease detection model for farmers in East Africa.” That number is comparable across projects, across hardware, and across time. If someone else contributes 600 OTUs to a different project, you know the scale of your contributions was equivalent — even if the underlying hardware was completely different.
This clarity is also essential for corporate sponsors and institutional partners. ESG reporting requires auditable metrics. Development finance institutions need standardised impact data. OTU provides a single, consistent number that can be tracked, reported, and verified.
Why this matters for researchers
Researchers applying to OpenToken describe their compute needs in familiar terms: the number of GPUs they need, the memory requirements, and the duration. We convert this into OTU during the allocation process, so that the researcher’s allocation is expressed in a unit that is independent of which specific hardware fulfils it.
This has a practical benefit. If a researcher is allocated 400 OTUs and we initially provision the work on RTX 4090 hardware, that allocation represents approximately 800 GPU-hours. If we later identify a more suitable machine, the same 400 OTU represents approximately 400 GPU-hours on the new hardware. The researcher’s entitlement stays the same. The hardware can change without renegotiation.
This flexibility is important because our provider landscape is evolving. As new partners come online and hardware generations turn over, the specific machines available to us will shift. OTU insulates researchers from that complexity. They receive a commitment measured in useful work, not in clock time on a particular machine.
OpenToken is a compute brokerage designed to ensure no innovative AI project fails for want of infrastructure. Learn more at www.opentoken.global.