OpenAI Cost Calculator
Estimate OpenAI API token spend with cached-input, Batch API, and long-context pricing rules.
Inputs
Choose the model tier you plan to use in production.
Average prompt size per API call — system prompt + context + user message. Typical ranges: simple chat 500–2,000 · RAG chatbot 2,000–8,000 · document analysis 10,000–100,000. A page of text ≈ 750 tokens.
Average response length per API call. Typical ranges: short answer 200–500 · paragraph 500–1,000 · long-form 1,000–4,000 tokens.
Total API calls per month across all users and jobs. 10 users × 3 sessions/day × 10 calls/session × 30 days = 9,000 requests/month.
Fraction of input tokens billed as cached reads. Cache writes and storage are not included. Use 0 if caching is disabled.
((2,000 fresh input × $5 + 0 cached-read input × $0.5 + 500 output × $30) / 1M × 10,000 req) × 12
Decision Summary
Enabling Prompt Cache with a 60% hit ratio could save $648.00/yr (22% reduction). Fix your system prompt at the start of every request and reuse it across calls.
Cost breakdown
| Item | Monthly | Yearly |
|---|---|---|
| Fresh input (2,000 tok/req × 10,000 req × $5/MTok) | $100.00 | $1,200.00 |
| Output spend (500 tok/req × 10,000 req × $30/MTok) | $150.00 | $1,800.00 |
| Total monthly spend | $250.00 | $3,000.00 |
Comparison
| Option | Monthly | Yearly |
|---|---|---|
| OpenAI GPT-5.6 Solcurrent | $250.00 | $3,000.00 |
| Claude Claude Sonnet 5 | $90.00 | $1,080.00 |
| Gemini Gemini 2.5 Pro | $75.00 | $900.00 |
| DeepSeek DeepSeek V4 Flashcheapest | $4.20 | $50.40 |
Pricing sources
Last verified 2026-08-03 · OpenAI official pricing developers.openai.com/api/docs/models/compare
Industry Benchmark
Pricing sources
Last verified 2026-08-03 · developers.openai.com/api/docs/models/compare developers.openai.com/api/docs/models/compare · platform.claude.com/docs/en/about-claude/pricing platform.claude.com/docs/en/about-claude/pricing · ai.google.dev/gemini-api/docs/pricing ai.google.dev/gemini-api/docs/pricing · api-docs.deepseek.com/quick_start/pricing api-docs.deepseek.com/quick_start/pricing
Trends & comparison
Trend
Comparison (monthly vs. yearly)
Official OpenAI rates used
Verified August 3, 2026: GPT-5 is $1.25/MTok input and $10 output; GPT-5 Mini is $0.25/$2; GPT-5 Nano is $0.05/$0.40. GPT-5.6 Sol is $5/$30, Terra is $2.50/$15, and Luna is $1/$6 before long-context pricing. Rates are stored in the shared pricing configuration and linked to OpenAI's official model documentation.
A reproducible workload example
A chatbot making 10,000 monthly calls with 2,000 input and 500 output tokens costs $75/month on GPT-5 before caching or Batch: 20 million input tokens at $1.25 plus 5 million output tokens at $10. The calculator exposes the same formula beside each result.
What the estimate includes
The estimate includes token usage for the selected model and the entered cached-read share. It excludes cache writes, cache storage, web search, containers, tool execution, fine-tuning, priority processing, taxes, credits, and enterprise agreements. Those items must be added from the applicable OpenAI price sheet or invoice.
Choosing a model economically
A lower token price does not prove equivalent quality. Compare candidate models on a representative evaluation set, then check latency, tool support, context limits, regional availability, and total non-token charges before moving production traffic.
Frequently asked questions
How is the monthly OpenAI API estimate calculated?▾
The calculator prices fresh input, cached-read input, and output tokens separately, then multiplies the per-request total by monthly request volume. Tool calls, web search, cache writes, storage, taxes, and contracted rates are not included.
When does GPT-5.6 long-context pricing apply?▾
For GPT-5.6 Sol, Terra, and Luna, requests above 272,000 input tokens use 2x input and 1.5x output rates for the entire request. The calculator applies that tier automatically.
How much can cached input save?▾
The result uses each model's published cached-input read rate only for the share entered as cache hits. Actual bills can also include cache-write or storage charges, so use provider billing data for final reconciliation.
When should I use the Batch API estimate?▾
Use it only for asynchronous jobs that qualify for OpenAI Batch pricing. The calculator applies the published 50% token-rate discount; it does not model service-specific charges.
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Compare verified first-party API prices on the same standard workload → AI Model Price Leaderboard