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LLM Inference Economics: Costs & Cloud Break-Even

Build vs. buy for LLM inference: cost per token, amortization and break-even for GPUs from RTX PRO 6000 to B300, side by side.

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Turn useful capacity and real costs into a comparison

Separate modeled token capacity from ownership, rental and API billing, then compare task quality before choosing.

AI-assisted learning visualization · schematic article explanation

Step 1 / 4Convert capacity into delivered work

A roofline estimates potential decode capacity, while utilization describes how much is used. Replace ideal token rates with measured workload throughput before treating the period’s token volume as a purchase forecast.

Costs & resourcesCurrent stepSelect a block to explain it
Validated serving capacity
Use measured throughput for the intended workload.
Useful tokens in the billing period
Demand and utilization determine delivered volume.
  1. Validated serving capacity Useful tokens in the billing period
    throughput × time × utilization
What to remember

Economics depends on delivered useful work, matching billing units and complete costs, not theoretical tokens alone.

Purchase and rental defaults are illustrative. The article’s API rates have an explicit verification date; prices need rechecking, and the model omits several full-system costs and workload effects.

Terms and the complete walkthrough
Utilization
The fraction of available serving capacity actually used.
Depreciation
Spreading an acquisition cost across an assumed useful period.
Cost per useful answer
Cost evaluated alongside task success, quality and service requirements.
  1. Convert capacity into delivered work

    A roofline estimates potential decode capacity, while utilization describes how much is used. Replace ideal token rates with measured workload throughput before treating the period’s token volume as a purchase forecast.

  2. Price the same deployment scope

    Ownership needs a full-system quote and operating assumptions; rental needs a real matching offer. GPU-only watts and depreciation omit CPU power, cooling, financing and other costs identified in the article.

  3. Align the API billing units

    An API can price input and output tokens differently, with additional cache and service rules. A price reference applied to an open-weight model does not establish that the two models are equally capable.

  4. Compare useful answers, not idle potential

    Use delivered volume as the cost denominator, then evaluate answer quality and latency on your tasks. With fixed ownership or rental costs, lower utilization raises allocated cost per delivered token even when peak hardware speed stays unchanged.

All connections

  • Validated serving capacity → Useful tokens in the billing period: throughput × time × utilization
  • Owned system costs → Comparable cost per volume: full ownership assumptions
  • Matched rental quote → Comparable cost per volume: actual rental terms
  • API input and output tariff → Comparable cost per volume: matched billed units
  • Useful tokens in the billing period → Comparable cost per volume: delivered denominator
  • Comparable cost per volume → Cost per useful answer: task-level comparison
Set your own pace. Pause at any time or select a step directly.

The calculator below compares a simplified decode capacity model with editable ownership, rental and API-price assumptions. It is a scenario tool: a cost result is meaningful only after entering a complete hardware quote, a real rental offer and measured serving throughput.

Physics and capacity

For small-batch dense decode, memory bandwidth divided by weight bytes is a weight-read throughput ceiling if weights and KV cache fit. The compute approximation is effective tensor FLOPS divided by twice the active parameter count. Both omit attention, prefill, routing overlap, scheduling, communication and runtime allocation details. The displayed batch crossover B* is where these two modeled ceilings meet; it is not an observed scheduling optimum. See the inference-math guide and break-even model.

Cost assumptions

GPU acquisition and cloud hourly prices in the tool are illustrative inputs, not verified market quotes. Replace them with a full-system purchase quote and a provider rate for the same GPU form factor, contract and region. The power calculation uses a simple assumed idle-to-peak curve and only GPU/board watts; the displayed 36-month depreciation excludes financing, non-GPU power and cooling. The output-token capacity estimate assumes continuous decode at the roofline with a user-selected efficiency and utilization. Prefill and traffic bursts can require additional capacity.

The API menu uses uncached standard text-token rates checked on 29 September 2026 against the vendors' own documentation: OpenAI, Anthropic, Google and xAI. Cached input, longer contexts, region, batch processing and tools can change the bill. The same selected API is used as a price reference for every open-weight row; the table makes no model-quality equivalence claim. Evaluate candidate models on your tasks before comparing cost per useful answer.

Economics

LLM inference economics beta

From physics to euros: how memory and compute cap your throughput, which model fits which hardware, what the hardware costs, and when owning beats renting — including the comparison against proprietary API pricing.

Token yield from this hardware

Operating batch size~624
Aggregate decode throughput24,916.3 tok/s
Tokens per month (100% utilization)64,583 M
Tokens per month (at 70% utilization)45,208 M

Operating point: min(B*, VRAM-capable batch), FP8 KV, continuous serving.

Monthly cost of owning

Amortized acquisition (36 mo)$236.11
Power (0.46 kW avg)$82.08
Housing + staff$100
Other opex$50
Total per month$468.19
Additional capital-cost estimate (excluded)$56.67
Own cost per 1M tokens$0.01

Scenario: acquisition amortized over 36 months; financing cost and non-GPU system power are excluded.

Which models fit which hardware (FP8 (1 B), 1× GPU)

Model
Qwen3-4B-Instruct-25074B✓✓✓✓✓✓✓✓✓✓✓✓✓✓✓
Qwen3-14B14B✓✓✓✓✓✓✓✓✓✓✓✓✓✓✓
Qwen3-32B32.76B✓✓✓✓✓✓✓✓✓✓✓✗✓✗✓
Qwen3-VL-8B-Instruct8B✓✓✓✓✓✓✓✓✓✓✓✓✓✓✓
Qwen3-30B-A3B30.5B✓✓✓✓✓✓✓✓✓✓✓~✓✗✓
Qwen3-Next-80B-A3B80B✓✓✓✓✗✓✓✓~~✗✗✗✗~
Qwen3.8-Flash-Next180B✓✗~✗✗✓✓~✗✗✗✗✗✗✗
Qwen3.8-27B27B✓✓✓✓✓✓✓✓✓✓✓~✓✗✓
Qwen3-235B-A22B235B~✗✗✗✗✓~✗✗✗✗✗✗✗✗
Llama 3.3-70B70B✓✓✓✓~✓✓✓✓✓✗✗~✗✓
gpt-oss-120B-A5B117B✓✓✓~✗✓✓✓✗✗✗✗✗✗✗
DeepSeek V3.2-671B-A37B671B✗✗✗✗✗✗✗✗✗✗✗✗✗✗✗
DeepSeek V4-Flash-0731284B✗✗✗✗✗✗✗✗✗✗✗✗✗✗✗
DeepSeek V4.1-Flash748B✗✗✗✗✗✗✗✗✗✗✗✗✗✗✗
GLM-5.2753B✗✗✗✗✗✗✗✗✗✗✗✗✗✗✗
Qwen3.6-35B-A3B35B✓✓✓✓✓✓✓✓✓✓✓✗✓✗✓
Nemotron Nano 9B v28.9B✓✓✓✓✓✓✓✓✓✓✓✓✓✓✓

✓ weights leave ≥15% raw capacity · ~ less than 15% · ✗ weights exceed capacity. KV and runtime memory are not included. Click a GPU header to select it. Format factor (3%) included.

Renting the same GPU in the cloud

Cloud rate used$2.20/h
Cloud monthly (24/7)$1,584
Cloud monthly (at 70% utilization)$1,108.8
Cloud cost per 1M tokens$0.02
Own vs cloud per monthOwn is $640.61 cheaper
Cross-over utilization27.22%

Hourly rental is an editable scenario input, not a provider quote. Billing minimums and contract terms vary.

API vs own hardware for your workload

Monthly token volume60 M
Gemini 3.8 Flash API cost per month$99
Decode-only minimum setups (6.94 tok/s)}1× setup
Own hardware cost per month$468.19
Operating savings before acquisition— (No operating savings)
Break-even (acquisition paid off)—

Uncached standard API rates checked Sept 29, 2026; edit for your plan. Hardware count is a decode-only lower bound, not a quality comparison.

Decode-only hardware cost vs selected API, per 1M output tokens

Open-weight cost = own-hardware cost at 70% utilization, FP8 (1 B) weights, FP8 KV.The selected API is a price reference for every row; model quality, prompt processing and operations are not matched.

Open-weight modelSelected API referenceAPI in / out ($/Mt)GPU size neededOwn $/MtAPI $/M output tokens at 30% out)Verdict
Qwen3-32B (dense)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0.03$5.5own −99.44%
Qwen3-VL-8B-Instruct (dense + vision)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0.01$5.5own −99.89%
Qwen3-14B (dense)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0.01$5.5own −99.81%
Qwen3-4B-Instruct-2507 (dense)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0$5.5own −99.95%
GLM-5.2 (753B-A40B, MLA + DSA)Gemini 3.8 Flash0.75 / 3.75No fit ≤8 GPUs at 2k—$5.5—
DeepSeek V4.1-Flash (552B-A16B + 196B Engram)Gemini 3.8 Flash0.75 / 3.75No fit ≤8 GPUs at 2k—$5.5—
DeepSeek V4-Flash-0731 (284B-A13B)Gemini 3.8 Flash0.75 / 3.754× RTX PRO 60$0.26$5.5own −95.32%
Qwen3.8-Flash-Next (125B-A6B + PLE + MTP)Gemini 3.8 Flash0.75 / 3.752× RTX PRO 60$0.31$5.5own −94.41%
Qwen3.8-27B (dense hybrid)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0.02$5.5own −99.64%
Qwen3.6-35B-A3B (hybrid MoE + vision)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0$5.5own −99.95%
Qwen3-235B-A22B (flagship MoE)Gemini 3.8 Flash0.75 / 3.753× RTX PRO 60$0.24$5.5own −95.61%
Llama 3.3-70B (dense)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0.22$5.5own −95.91%
gpt-oss-120B-A5B (MoE, MXFP4)Gemini 3.8 Flash0.75 / 3.752× RTX PRO 60$0.03$5.5own −99.5%
DeepSeek V3.2-671B-A37B (MoE + MLA)Gemini 3.8 Flash0.75 / 3.758× RTX PRO 60$0.16$5.5own −97.05%
Qwen3-Next-80B-A3B (hybrid MoE)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0.04$5.5own −99.35%
Nemotron Nano 9B v2 (hybrid Mamba)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0.01$5.5own −99.88%
Qwen3-30B-A3B (MoE)Gemini 3.8 Flash0.75 / 3.751× RTX PRO 60$0.01$5.5own −99.81%

GPU purchase and rental prices are illustrative inputs, not verified offers. Enter your complete-system quote and rental rate. API prices are uncached standard rates checked Sept 29, 2026; long-context, regional, caching, batch and tool charges are excluded. Hardware throughput is a simplified decode roofline; prefill, attention, scheduling, networking, CPU work and non-GPU power are not modeled.

Limitations

  • The efficiency and utilization inputs are user assumptions; there is no universal percentage of peak that every stack achieves.
  • Purchase and rental defaults are scenario inputs. API rates need checking again before a buying decision.
  • Prefill, scheduling, networking, CPU work, full-system power, taxes and financing are omitted; compare actual quotes and measured workloads.