GPT-6.1 Sol vs Claude Sonnet 5.5

At 6,000 chat requests per month (1,500 in / 400 out), the two are within a few percent: $42 versus $42.

SpecGPT-6.1 SolClaude Sonnet 5.5
VendorOpenAIAnthropic
Input / 1M tokens$2$2
Output / 1M tokens$10$10
Cached input / 1M$0.100$0.100
Context window1.1M tokens1M tokens
Max output128K tokens128K tokens
Input modalitiestext, imagetext, image
Released——
Cost per 1M cached reads$0.100$0.100

Published list prices, last verified Oct 15, 2026. Source links are on each model's page.

Cost at three workloads

WorkloadGPT-6.1 SolClaude Sonnet 5.5Difference
Customer-support reply (1,500 in / 400 out) $0.0070$0.0070 —
Document summary (20,000 in / 1,000 out) $0.050$0.050 —
Code review pass (8,000 in / 1,500 out) $0.031$0.031 —

Which one fits your workload

  • Long context: GPT-6.1 Sol accepts more — 1.1M versus 1M tokens. If your retrieved context regularly exceeds 1M, only one of these will hold it.
  • Long answers: output is priced the same per token, so the difference is purely how many tokens you generate.
  • High-volume, short answers: input is priced identically.
  • Caching: at least one of these vendors publishes a discounted cached-input rate; if you resend the same system prompt and context, model the cache-hit rate or you will overestimate cost.

This comparison uses published price and specification data only. It does not rank output quality — run your own evaluation on your own prompts before switching a production default.

Price either one for your traffic

Open the LLM cost calculator