Claude vs GPT-6: What a Million Tokens Costs
Anthropic and OpenAI price their line-ups at the same three points. Here is where the real differences hide, with a calculator for your own workload.
October 19, 2026 · AI · Comparison
Compare Anthropic's Claude 5.5 line-up with OpenAI's GPT-6 line-up and something odd stands out: at three tiers out of four, the list prices are identical. The real differences are further down the price sheet, in caching, long prompts, and what each vendor will discount.
All prices are USD per million tokens from each vendor's own pricing page, checked on 19 October 2026. Sources are at the end.
Three price points, two vendors
| Tier | Claude | GPT | Input | Output |
|---|---|---|---|---|
| Small | Haiku 5.5 | GPT-6 Luna | $0.10 | $0.50 |
| Mid | Sonnet 5.5 | GPT-6.1 Sol | $2 | $10 |
| Frontier | Opus 5.5 | none | $4 | $20 |
| Flagship | Fable 5.1 | GPT-6 Astra | $10 | $50 |
Opus 5.5 sits between the mid and flagship tiers with no direct OpenAI match. Everywhere else, picking a vendor on headline price alone gets you nowhere, because there is no headline difference to find.
The whole price sheet
Lapis is Anthropic and terracotta is OpenAI. Switch between prices with the tabs, and try the log scale: it is the only way to see the small tier next to the flagship one.
Where the differences hide
Cached input. When part of a prompt repeats, both vendors charge much less for the repeated part. At the small and mid tiers the cached prices match too. At the flagship tier they do not: Fable 5.1 charges $0.25 for a cache hit and Astra charges $1.00.
Long prompts. Anthropic charges one rate across the whole 1M-token window for Fable, Opus, and Sonnet, but Haiku 5.5 moves to a higher band above 100,000 prompt tokens. OpenAI moves all three GPT-6 models to a higher band above 272,000.
Batch work. Both vendors give roughly half off for jobs that can wait. Anthropic lists a batch rate for every current model. OpenAI lists Flex and Batch rates for Sol and Astra, and none for Luna.
A token is not a universal unit
Price per token is only a fair comparison if both models count tokens the same way, and they do not. Anthropic notes that Claude 4.7 and later models use a newer tokenizer that produces about 30% more tokens for the same text than earlier models, and that the count for any request depends on the model's tokenizer, the language, and the type of content.
So the number that matters is cost per task, not cost per token. Count tokens for your own text on each model before trusting any table, including this one.
Try your own workload
Pick an example or set your own numbers. The calculator applies each model's list price, switches to the higher price band for long prompts, and applies batch rates where they exist. Try the "Huge prompts" example to watch the higher price bands apply: a 300,000-token prompt is over both Haiku 5.5's 100,000-token threshold and the GPT-6 models' 272,000-token one.
What the cheap tier buys
The small tier is where the two vendors are closest on price, and where the most work now gets done. Anthropic's Haiku 5.5 announcement compares Haiku 5.5 with the previous Haiku, with OpenAI's GPT-6 Luna, and with Sonnet 5.5 for reference. These are Anthropic's own published results, so read them as a vendor's numbers and not an independent test.
The tabs are the benchmarks: GDPval-AA, AA-Briefcase, OSWorld 2.1 (offline subset), Humanity's Last Exam (no tools), Terminal-Bench 4.0, FrontierCode 1.1, and Chartography (no tools). Haiku 5.5 and Luna list for exactly the same price, so on these tests the question is what you get for it. The wider lesson is that a model one tier up can still be far ahead, as Sonnet 5.5 is here. Whether that gap is worth $2 against $0.10 depends on the task.
Picking between them
Match the job to the tier first, then compare vendors inside the tier. The pairings follow each vendor's own descriptions of what its models are for:
What we take from it
At list prices the two vendors are close to twins, so a decision between them comes down to details that a headline price hides:
- How much of your prompt repeats. Caching decides your real input cost, and it is where Fable and Astra part ways.
- How long your prompts get. Haiku 5.5 changes price at 100,000 tokens and the GPT-6 models at 272,000.
- Whether the work can wait. Batch pricing roughly halves the bill where it is offered.
- What your own tests say. A benchmark from a vendor is a starting point. Run your own task on each candidate before committing.
These are list prices. Discounts negotiated at volume, and the cost of the tokens a model spends thinking, are not on any price sheet.
If you want to see real numbers while you work, Crooli AI tracks token usage and estimated cost at both message and conversation level, across whichever providers you connect.
For the details on each side, see our Claude 5.5 field guide and our Codex explainer.