OpenAI API Pricing 2026:
GPT-6 Astra, GPT-6.1 Sol, GPT-6 Luna & Current Models
Current OpenAI API pricing for the GPT-6 family, with cached-input, long-context and Batch API rates, plus what happened to GPT-5.4 and GPT-4o. Last verified: 2026-10-01.
GPT-6 Family — Current Flagship Models
| Model | Input / 1M tokens | Cached input / 1M | Output / 1M tokens | Best for |
|---|---|---|---|---|
| GPT-6 Astra | $10.00 | $1.00 | $50.00 | Hardest reasoning, research and agentic tasks |
| GPT-6.1 Sol | $2.00 | $0.10 | $10.00 | Everyday production default: coding, analysis, agents |
| GPT-6 Luna | $0.10 | $0.01 | $0.50 | Ultra-high volume, simple tasks |
All three models have a 1.05M-token context window and up to 128K output tokens. Prices above are OpenAI's standard tier for prompts up to 272K input tokens.
Specialised Models
OpenAI also lists its "Daybreak" cyber models separately: GPT-5.6 Sol at $4.00/M input and $20.00/M output (promotional pricing at least through November 21, 2026) and GPT-5.6 Cyber at $12.50/$75.00.
What Happened to GPT-5.4 and GPT-4o?
GPT-5.4, GPT-5.4 mini, GPT-5.4 nano, GPT-4o and GPT-4o mini no longer appear on OpenAI's API pricing page (checked October 2026). For reference, their last published prices when we verified them in April 2026 were:
| Model (April 2026 prices) | Input / 1M | Output / 1M | Closest current model |
|---|---|---|---|
| GPT-5.4 | $2.50 | $15.00 | GPT-6.1 Sol ($2/$10) or GPT-6 Astra |
| GPT-5.4 mini | $0.75 | $4.50 | GPT-6 Luna or GPT-6.1 Sol |
| GPT-5.4 nano | $0.20 | $1.25 | GPT-6 Luna ($0.10/$0.50) |
| GPT-4o | $2.50 | $10.00 | GPT-6.1 Sol |
| GPT-4o mini | $0.15 | $0.60 | GPT-6 Luna |
If you still run one of these models, check its status in your OpenAI dashboard. For new projects, start with the GPT-6 family: GPT-6 Luna is cheaper than GPT-4o mini on input ($0.10 vs $0.15), and GPT-6.1 Sol undercuts GPT-5.4 on both input and output.
OpenAI Batch API — 50% Discount for Non-Real-Time Work
OpenAI's Batch (and Flex) pricing is 50% lower than standard for asynchronous workloads such as evals, data processing and classification. Batches complete within 24 hours.
| Model | Standard Input | Batch Input | Standard Output | Batch Output |
|---|---|---|---|---|
| GPT-6 Astra | $10.00 | $5.00 | $50.00 | $25.00 |
| GPT-6.1 Sol | $2.00 | $1.00 | $10.00 | $5.00 |
| GPT-6 Luna | $0.10 | $0.05 | $0.50 | $0.25 |
Which OpenAI Model Is Best for Cost-Sensitive Apps?
| Use case | Recommended model | Reason |
|---|---|---|
| Hardest reasoning and research | GPT-6 Astra | Top quality; 5× the price of Sol, so reserve it for tasks that need it |
| Coding, analysis, balanced production work | GPT-6.1 Sol | $2/$10 with very cheap cached input ($0.10/M) |
| High-volume simple tasks | GPT-6 Luna | Cheapest OpenAI model at $0.10/M input |
| Async classification / evals | Batch API (any model) | 50% off, 24h turnaround |
Model Selection by Use Case
- Customer support (volume, simple): GPT-6 Luna
- Customer support (complex, nuanced): GPT-6.1 Sol
- Code generation / review: GPT-6.1 Sol; GPT-6 Astra for the hardest problems
- Document summarization (long): GPT-6.1 Sol — keep prompts under 272K tokens to avoid long-context rates
- Content generation at scale: GPT-6.1 Sol + Batch API
- Classification pipeline: GPT-6 Luna + Batch API
OpenAI API Access
- Sign up at platform.openai.com — immediate access, no approval needed
- Pay-as-you-go — no monthly minimum
- Enterprise: custom terms and dedicated capacity — contact OpenAI sales
Frequently Asked Questions
What is the difference between OpenAI API and ChatGPT?
The OpenAI API is the developer-facing service where you pay per token based on your application usage. ChatGPT is the consumer web and mobile product with flat-rate subscriptions. Building a product requires the API, not a ChatGPT subscription.
Is GPT-6.1 Sol cheaper than Claude Sonnet 5.5?
They cost the same per token: $2.00/M input and $10.00/M output. Sol's cached input is cheaper ($0.10/M vs $0.20/M for Sonnet 5.5), which helps workloads with large repeated prompts; Sonnet 5.5 has a 1M context window versus Sol's 1.05M.
How does the OpenAI Batch API save money?
Batch pricing is 50% lower than standard for jobs that can wait up to 24 hours. It suits non-latency-sensitive tasks like evals, bulk classification, content processing and dataset enrichment.
Does OpenAI charge extra for long prompts?
Yes, above 272K input tokens. Such requests are billed at 2× the input and cache rates and 1.5× the output rate. Below that threshold the standard prices apply, up to the 1.05M-token context window.
Calculate Your OpenAI API Costs
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