OpenAI vs Anthropic Pricing 2026:
GPT-6 vs Claude 5.5 Full Comparison
Complete pricing comparison between OpenAI (GPT-6 Luna, GPT-6.1 Sol, GPT-6 Astra) and Anthropic (Claude Haiku 5.5, Sonnet 5.5, Opus 5.5, Fable 5.1) across tiers, context windows, batch pricing and caching. Includes which provider wins by use case. Last verified: 2026-10-16.
It depends on the tier and the prompt length. At the budget end the list prices now match: GPT-6 Luna and Claude Haiku 5.5 both cost $0.10/$0.50 per million tokens, though Haiku 5.5 rises to $0.50/$2.50 for prompts over 100K tokens. In the middle the two are also identical — GPT-6.1 Sol and Claude Sonnet 5.5 both cost $2/$10. At the premium end Anthropic is cheaper: Claude Opus 5.5 costs $4/$20 versus $10/$50 for GPT-6 Astra, while the top models (Astra and Claude Fable 5.1) match at $10/$50.
Model Tier Comparison — Standard Pricing
| Tier | OpenAI Model | Input / 1M | Output / 1M | Anthropic Model | Input / 1M | Output / 1M |
|---|---|---|---|---|---|---|
| Budget | GPT-6 Luna | $0.10 | $0.50 | Claude Haiku 5.5* | $0.10 | $0.50 |
| Mid | GPT-6.1 Sol | $2.00 | $10.00 | Claude Sonnet 5.5 | $2.00 | $10.00 |
| Premium | GPT-6 Astra | $10.00 | $50.00 | Claude Opus 5.5 | $4.00 | $20.00 |
| Frontier | GPT-6 Astra | $10.00 | $50.00 | Claude Fable 5.1 | $10.00 | $50.00 |
* Claude Haiku 5.5: $0.10/$0.50 for prompts up to 100,000 tokens, $0.50/$2.50 above. It replaced Claude Haiku 4.5 ($1/$5), now a legacy model.
OpenAI has three current GPT-6 models and Anthropic four, so Astra appears against both Opus 5.5 and Fable 5.1. GPT-6 prices apply up to 272K input tokens; longer prompts cost 2× input and 1.5× output.
Batch API Pricing Comparison
| Model | Batch Input / 1M | Batch Output / 1M | Savings vs Standard |
|---|---|---|---|
| GPT-6 Luna (batch) | $0.05 | $0.25 | 50% off standard |
| GPT-6.1 Sol (batch) | $1.00 | $5.00 | 50% off standard |
| GPT-6 Astra (batch) | $5.00 | $25.00 | 50% off standard |
| Claude Haiku 5.5 (batch, ≤100K prompt) | $0.05 | $0.25 | 50% off standard |
| Claude Sonnet 5.5 (batch) | $1.00 | $5.00 | 50% off standard |
| Claude Opus 5.5 (batch) | $2.00 | $10.00 | 50% off standard |
Prompt Caching: Both Providers Discount Repeated Context
| Model | Standard Input / 1M | Cached Input / 1M | Discount |
|---|---|---|---|
| GPT-6 Luna | $0.10 | $0.01 | 90% |
| GPT-6.1 Sol | $2.00 | $0.10 | 95% |
| GPT-6 Astra | $10.00 | $1.00 | 90% |
| Claude Haiku 5.5 | $0.10 | $0.01 | 90% |
| Claude Sonnet 5.5 | $2.00 | $0.10 | 95% |
| Claude Opus 5.5 | $4.00 | $0.20 | 95% |
| Claude Fable 5.1 | $10.00 | $0.25 | 97.5% |
Caching is no longer an Anthropic-only advantage: in the mid tier GPT-6.1 Sol and Claude Sonnet 5.5 both charge $0.10/M for cached input, while at the top end Claude Opus 5.5 ($0.20/M) and Fable 5.1 ($0.25/M) cache far more cheaply than GPT-6 Astra ($1.00/M). On OpenAI, writing to the cache costs 1.25× the normal input rate.
Context Window Comparison
| Model | Context Window | Pricing Note |
|---|---|---|
| GPT-6 Astra / Sol / Luna | 1.05M tokens | Higher rates above 272K input tokens (2× input, 1.5× output) |
| Claude Fable 5.1 / Opus 5.5 / Sonnet 5.5 | 1M tokens | Single per-token rate |
| Claude Haiku 5.5 | 1M tokens | Higher rates above 100K prompt tokens ($0.50/$2.50) |
Winner by Use Case
Which Provider Should You Choose?
Choose OpenAI if:
- Your high-volume workload sends long prompts — above 100K tokens GPT-6 Luna stays at $0.10/$0.50 while Claude Haiku 5.5 rises to $0.50/$2.50
- You need the OpenAI ecosystem: Assistants, fine-tuning, Azure OpenAI and integrations that default to OpenAI
Choose Anthropic if:
- You need premium quality at a lower price — Claude Opus 5.5 is 60% cheaper than GPT-6 Astra
- You send very long prompts to the mid or premium tier — Sonnet, Opus and Fable have one rate for the whole 1M context, while GPT-6 charges more above 272K tokens
- You are building long-running agents and want Anthropic's tooling and Messages API
- Your team already runs evaluations showing Claude performs better on your tasks
Frequently Asked Questions
Is OpenAI cheaper than Anthropic in 2026?
Mostly not. GPT-6 Luna and Claude Haiku 5.5 have the same list price ($0.10/$0.50) for prompts up to 100K tokens; above that Luna is cheaper. GPT-6.1 Sol and Claude Sonnet 5.5 cost the same ($2/$10), and Claude Opus 5.5 ($4/$20) is cheaper than GPT-6 Astra ($10/$50). The older Claude Haiku 4.5 ($1/$5) is ten times more expensive than either budget model.
Which is better for coding?
Both providers' mid-tier models — GPT-6.1 Sol and Claude Sonnet 5.5 — are positioned for coding and agents at the same price, so run a short evaluation on your own repository before committing. For the hardest work, compare Claude Opus 5.5 with GPT-6 Astra: Opus costs less than half as much.
Can I switch between OpenAI and Anthropic?
Yes, with moderate engineering effort. The API formats differ (OpenAI's APIs vs Anthropic's Messages API), but frameworks like LangChain, LlamaIndex and LiteLLM abstract both. Re-run your evals after switching, because prompts tuned for one model rarely transfer perfectly.
Do both support vision / multimodal input?
Yes, both providers' current models accept image input. Image pricing varies by resolution and is charged in addition to text token pricing. Check each provider's current documentation for image pricing specifics.
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