Claude Sonnet 5.5 vs GPT-6.1 Sol: pricing and benchmarks
Both charge $2.00 per 1M input tokens. Both charge $10.00 per 1M output tokens. On our document Q&A workload both models cost $1,100 a month. Epoch AI has not published a capability index score for Claude Sonnet 5.5 and GPT-6.1 Sol yet.
Prices verified October 3, 2026.
Which should you choose?
Epoch AI has not published a capability index score for Claude Sonnet 5.5 and GPT-6.1 Sol yet.
Both cost $4.00 per 1M tokens at a 3:1 input-to-output mix.
Pricing and specs
| Claude Sonnet 5.5 | GPT-6.1 Sol | |
|---|---|---|
| Provider | Anthropic | OpenAI |
| API model ID | claude-sonnet-5-5 | gpt-6.1-sol |
| Input / 1M tokens | $2.00 | $2.00 |
| Cached input / 1M tokens | $0.20 | $0.10 |
| Output / 1M tokens | $10.00 | $10.00 |
| Long-context rates | — | $4.00 in / $15.00 out above 272K prompt tokens |
| Context window | 1M tokens | 1.05M tokens |
| Max output | 128K tokens | 128K tokens |
| Batch discount | 50% off | 50% off |
Monthly cost for real workloads
| Workload | Claude Sonnet 5.5 | GPT-6.1 Sol | Difference |
|---|---|---|---|
Support chatbot 100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each. | $700.00 | $700.00 | Same |
Document Q&A (RAG) 50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each. | $1,100 | $1,100 | Same |
Coding agent 10,000 agent steps a month, ~40,000 input tokens each (70% read from the prompt cache) and ~2,000 output tokens. | $496.00 | $468.00 | GPT-6.1 Sol 6% cheaper |
Estimates use standard list prices and ignore cache-write surcharges. Different tokenizers can count the same text differently, so test with your own prompts.
Claude Sonnet 5.5 vs GPT-6.1 Sol cost calculator
- $1,100/mo$0.02 / request
- Claude Sonnet 5.5Anthropic$1,100/mo$0.02 / request
Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.
Claude Sonnet 5.5 pricing notes
Anthropic’s fast mid-tier model, successor to Claude Sonnet 5 at the same price.
- Cache writes cost $2.50 (5-minute cache) or $4 (1-hour cache) per 1M tokens.
- US-only inference (inference_geo: "us") costs 1.1x.
GPT-6.1 Sol pricing notes
OpenAI’s update to GPT-6 Sol, with near-Astra performance for complex work at a lower cost.
- Cached input costs $0.10 per 1M tokens, half of GPT-6 Sol’s $0.20.
- Cache writes are billed at $2.50 per 1M tokens.
- Prompts over 272K input tokens use the long-context rates.
- Fast mode costs 2x the standard rate; Flex costs half.
Frequently asked questions
- Is Claude Sonnet 5.5 cheaper than GPT-6.1 Sol?
- Both charge $2.00 per 1M input tokens. Both charge $10.00 per 1M output tokens. On our document Q&A workload both models cost $1,100 a month.
- Which is more capable, Claude Sonnet 5.5 or GPT-6.1 Sol?
- Epoch AI has not published a capability index score for Claude Sonnet 5.5 and GPT-6.1 Sol yet.
- How much does Claude Sonnet 5.5 cost per 1M tokens?
- Claude Sonnet 5.5 costs $2.00 per 1M input tokens and $10.00 per 1M output tokens, and $0.20 per 1M cached input tokens on Anthropic’s standard tier.
- How much does GPT-6.1 Sol cost per 1M tokens?
- GPT-6.1 Sol costs $2.00 per 1M input tokens and $10.00 per 1M output tokens, and $0.10 per 1M cached input tokens on OpenAI’s standard tier.
- Which has the larger context window, Claude Sonnet 5.5 or GPT-6.1 Sol?
- GPT-6.1 Sol has the larger context window: 1.05M tokens versus 1M for Claude Sonnet 5.5.