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PricesCalculators → RAG document Q&A

RAG document Q&A: LLM cost calculator

Retrieval-augmented Q&A over a private corpus: several thousand tokens of retrieved chunks per question. Input dominates cost, and retrieved chunks change per query so cache hit rates stay low.

Default profile: 8,000 in / 600 out per call · 20,000 calls/mo · 25% cached
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Cheapest option
GPT-5.6 Luna
$19.60/mo
Priciest option
GPT-5.6 Cyber
$2,450/mo
Annual gap
$29,165
same workload, different model

Every model on this workload

Input is 93% of tokens here, so input pricing dominates. Cache applied at 25%.

ModelIn /1MOut /1MNo cacheMonthlyvs best
GPT-5.6 Luna OpenAI$0.100$0.600$23.20$19.60cheapest
Gemini 2.5 Flash-Lite Google$0.100$0.400$20.80$20.801.1x
Gemini 3.1 Flash-Lite Google$0.250$1.500$58.00$58.003.0x
Gemini 3.5 Flash-Lite Google$0.300$2.500$78.00$78.004.0x
Gemini 2.5 Flash Google$0.300$2.500$78.00$78.004.0x
Gemini 3.7 Flash Google$0.750$3.750$165.00$165.008.4x
Gemini 3.6 Flash Google$0.750$3.750$165.00$165.008.4x
Claude Haiku 4.5 Anthropic$1.000$5.000$220.00$184.009.4x
GPT-5.6 Terra OpenAI$1.000$6.000$232.00$196.0010.0x
Gemini 2.5 Pro Google$1.250$10.00$320.00$320.0016.3x
Gemini 3.5 Flash Google$1.500$9.000$348.00$348.0017.8x
Claude Sonnet 5 Anthropic$2.000$10.00$440.00$368.0018.8x
GPT-5.3 Codex OpenAI$1.750$14.00$448.00$385.0019.6x
Gemini 3.1 Pro Google$2.000$12.00$464.00$464.0023.7x
GPT-5.6 Sol OpenAI$2.500$15.00$580.00$490.0025.0x
Claude Sonnet 4.6 Anthropic$3.000$15.00$660.00$552.0028.2x
Claude Opus 5 Anthropic$5.000$25.00$1,100$920.0046.9x
Claude Opus 4.5 Anthropic$5.000$25.00$1,100$920.0046.9x
GPT chat-latest OpenAI$5.000$30.00$1,160$980.0050.0x
Claude Fable 5 Anthropic$10.00$50.00$2,200$1,84093.9x
Claude Mythos 5 Anthropic$10.00$50.00$2,200$1,84093.9x
GPT-5.6 Cyber OpenAI$12.50$75.00$2,900$2,450125.0x
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Adjust the assumptions

The defaults above are a reasonable starting profile, not your profile. Change them.

Cost calculator

Enter your own numbers, or start from a workload preset. Costs are monthly and update as you type.

Cheapest model
Cheapest → priciest spread
ModelIn /1MOut /1MMonthlyvs best

Cutting this bill in practice

Switching from GPT-5.6 Cyber to GPT-5.6 Luna on this workload is worth $29,165 a year. Two things make a number like that collectible rather than hypothetical: being able to change model without an integration rewrite, and knowing when the volume justifies leaving per-token pricing entirely.

Switch models without rewriting your integration

The savings on this page are only real if you can actually move traffic to the cheaper model. Aggregators and gateways sit in front of multiple providers so that switch is a configuration change.

Run open-weight models on rented GPUs

Past a certain monthly volume, renting a GPU beats paying per token — but only for workloads where an open-weight model is good enough, and where utilization is high enough to amortize idle time.

Other workloads

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