Not Diamond vs Vercel AI Gateway
Both are llm gateways tools. Here is how they actually differ on price, billing model and deployment.
Not Diamond
A model router that recommends rather than proxies - it tells your gateway which model to call and gets out of the way. That architecture means no request-path dependency, which nothing else in this category offers.
Vercel AI Gateway
No markup on tokens and $5 of free credits a month per team. The details worth knowing are that BYOK is paid-tier only, and zero data retention is a metered add-on at $0.10 per 1,000 requests.
| Not Diamond | Vercel AI Gateway | |
|---|---|---|
| Category | LLM Gateways | LLM Gateways |
| Our rating | 4/5 | 4/5 |
| Starting price | Conflicting reports | $0 plus provider list price |
| Billing meter | No usage metering | No usage metering |
| Free plan | Yes | Yes |
| Free self-hosting | No or paid tier only | No or paid tier only |
| Best for | Teams already running a gateway who want smarter per-request model selection without putting another vendor in the request path, particularly for coding agents where model spend is high and uncontrolled. | Teams already deploying on Vercel who want provider-agnostic model access at list price with no markup, and who do not need governance features that carry a per-request charge. |
Our verdict on Not Diamond
Not Diamond is architecturally the most interesting thing in this category because it declines to be a gateway. Integrations are stack-agnostic through its API, and recommendations are executed in your own model gateway and harness - so it tells you which model to call and gets out of the way. Every other router in this category is a proxy, which means adopting it creates a request-path dependency and a new availability risk. Not Diamond has neither. It composes with LiteLLM, Vercel, Cloudflare or your own proxy rather than replacing any of them, which makes it unusually low-commitment to try. The product is a pre-trained Chat router, a Code router aimed at coding-agent cost currently in early access, and custom routers trained on your own data. That last one matters most, because the weakness of generic routing is that your workload is not the benchmark it was tuned on. The unsatisfying part is pricing, where sources directly contradict each other, and the fact that the most differentiated capability is still early access.
Full Not Diamond review →Our verdict on Vercel AI Gateway
Vercel AI Gateway takes no markup on tokens, which puts it in the right half of this category immediately. You pay provider list price from prepaid credits, every team gets $5 a month in credits that refresh every 30 days, and platform seats are free on Hobby - so a solo developer pays nothing for the gateway itself. Against OpenRouter's 5.5% with no volume discounts, that difference compounds indefinitely. Three details deserve attention before you commit. BYOK is paid-tier only, so using your own provider keys requires the $20 per seat plan. Failed BYOK requests fall back to system credentials and are charged against your balance, which is the kind of thing you discover on an invoice rather than in documentation. And zero data retention is not a default - it is a team-wide add-on metered at $0.10 per 1,000 successful requests, with provider allowlists priced the same way. Charging per request for privacy and for basic governance is an unusual choice and worth modelling if either matters to you.
Full Vercel AI Gateway review →Frequently Asked Questions
What is the main difference between Not Diamond and Vercel AI Gateway?
Not Diamond: Teams already running a gateway who want smarter per-request model selection without putting another vendor in the request path, particularly for coding agents where model spend is high and uncontrolled. Vercel AI Gateway: Teams already deploying on Vercel who want provider-agnostic model access at list price with no markup, and who do not need governance features that carry a per-request charge. Both sit in LLM Gateways, so the decision usually comes down to billing model and deployment rather than raw capability.
Which is cheaper, Not Diamond or Vercel AI Gateway?
It depends entirely on your workload shape, because they meter differently - Not Diamond bills on no usage metering and Vercel AI Gateway bills on no usage metering. Published starting prices are Conflicting reports and $0 plus provider list price respectively, but those numbers are not comparable until you apply them to the same traffic. Use our cost calculator to model both against your own request volume and span count.
Can I self-host Not Diamond or Vercel AI Gateway?
Not Diamond: No or paid tier only. Vercel AI Gateway: No or paid tier only. Free self-hosting means no licence fee, not no cost - you still own the infrastructure, upgrades and on-call.