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Open-weight model total cost of ownership.

10 July 2026

By the LLM CFO team

Llama 8B is free. Running Llama 8B on an H100 is not. The calculation looks simple—an H100 rents for ~$2 / hour on Lambda Labs or RunPod, Llama 8B serves ~500 requests/second, so your cost per request is $2 / 1800 = $0.0011. But the real math is messier. You pay for idle time when traffic dips. You pay for quantization, optimizations, and eval runs that don't generate revenue. You pay for tail latency and retry loops. Self-hosting an open-weight model is cheaper than a frontier API only above a specific utilization threshold; below it, you're paying rent on unused GPUs.

The break-even calculation

Start with your hourly GPU cost and your expected throughput. On Lambda Labs, an H100 costs $2 / hour. Llama 8B with vLLM reaches 200–400 req/s, depending on batch size and token length. Let's assume 300 req/s as a realistic middle ground, averaging 100 tokens per request, so 30k tokens / sec.

At that throughput, your per-1M-token cost is:

Claude 3.5 Sonnet on Bedrock costs $3.00 / 1M input tokens, $15.00 / 1M output. If your workload is mostly input (e.g., classification, retrieval), you're paying $3.00 / 1M and your self-hosted cost is $18.70. Bedrock wins by 6x. If your workload is mostly output (e.g., generation), you're paying $15.00 / 1M and your self-hosted cost is $18.70. They're comparable, but you haven't included ops yet.

Hidden costs of self-hosting

Cost categoryTypical rangeImpact
Idle GPU time (traffic variance)20–40% of GPU costIf you average 300 req/s but peak at 100 and trough at 50, you over-provision and pay for empty capacity.
Model quantization and tuning$2k–$10k one-timeAmortize over expected lifetime; adds setup delay.
Eval and monitoring10–15% of GPU costRunning test suites, LLM-as-judge scoring, latency tracking.
DevOps and incident response0.5–1.0 FTE per clusterAssumes <5 H100s. Larger clusters need more; smaller might share ops with other workloads.
Egress and data transfer$0.10 per GB (cloud to cloud)Pulling training data, syncing checkpoints, logs. Often overlooked.
Quantization decode overhead2–5% latency tax4-bit quantization saves GPU memory but adds decode latency. Some requests may timeout.

Real-world break-even points

The math changes based on model size and utilization:

Note: these assume 100 average tokens per request. High-volume, low-context workloads (classification, tagging, retrieval) push the break-even point much higher. Long-context workloads (summarization, reasoning) favor self-hosting earlier.

When to self-host

When NOT to self-host

The hybrid approach

Most scaled teams don't pick one or the other. They run low-cost, high-volume workloads on self-hosted Llama (e.g., 1M+ requests/month of classification or retrieval), route high-quality or bursty workloads to Bedrock / Azure OpenAI, and use fine-tuned models on APIs (e.g., Azure OpenAI fine-tuned GPT-4) for ultra-sensitive tasks. This requires a routing gateway (LiteLLM, custom logic) that picks the right model based on cost targets, quality requirements, and current load. The operational overhead is real, but the cost efficiency is usually 30–50% better than staying on a single provider.

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