Claude Sonnet 5.5 vs GPT-6.1 Terra
Claude Sonnet 5.5 leads the LLM Stats Score 57.9 to 47.5. GPT-6.1 Terra is 2.0x cheaper per token.
Anthropic · OpenAI · Updated for 2026
Which is better?
Claude Sonnet 5.5 leads the overall LLM Stats Score 57.9 to 47.5, ranking #3 overall.
In the 4 individual benchmarks reported for both models, Claude Sonnet 5.5 wins 4; this is a narrower head-to-head signal than the composite indexes.
On price, GPT-6.1 Terra is roughly 2.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-6.1 Terra also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Claude Sonnet 5.5
- overall performance matters — it scores 57.9 and ranks #3 on LLM Stats
- you value its reported benchmark strengths — it wins 4 of 4 exact shared results
Choose GPT-6.1 Terra
- cost matters — it's about 2.0x cheaper per token
- you process long inputs — it offers a 1,050,000 token context window
- you want the most recent training data — it shipped Oct 2026
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
47 reported for Claude Sonnet 5.5 · 8 for GPT-6.1 Terra
Claude Sonnet 5.5 outperforms in 4 benchmarks (HealthBench, HealthBench Professional, Terminal-Bench 4.0, Terminal-Bench-Science 0.1), while GPT-6.1 Terra is better at 0 benchmarks.
Claude Sonnet 5.5 significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Sonnet 5.5 ($2.00/1M tokens) is 2.0x more expensive than GPT-6.1 Terra ($1.00/1M tokens).
For output processing, Claude Sonnet 5.5 ($10.00/1M tokens) is 2.0x more expensive than GPT-6.1 Terra ($5.00/1M tokens).
In conclusion, Claude Sonnet 5.5 is more expensive than GPT-6.1 Terra.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-6.1 Terra accepts 1,050,000 input tokens compared to Claude Sonnet 5.5's 1,000,000 tokens. Both models can generate responses up to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
Both Claude Sonnet 5.5 and GPT-6.1 Terra support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Sonnet 5.5
GPT-6.1 Terra
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Claude Sonnet 5.5 was released on 2026-09-28, while GPT-6.1 Terra was released on 2026-10-26.
GPT-6.1 Terra is 1 month newer than Claude Sonnet 5.5.
Sep 28, 2026
3 weeks ago
Oct 26, 2026
-1 days ago
4w newerKnowledge Cutoff
When training data ends
Both models have the same knowledge cutoff date of 2026-06-01.
They should have similar awareness of historical events and information up to this date.
Jun 2026
Jun 2026
Provider Availability
Claude Sonnet 5.5 is available from Anthropic. GPT-6.1 Terra is available from OpenAI.
Claude Sonnet 5.5
GPT-6.1 Terra
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Sonnet 5.5 and GPT-6.1 Terra side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Sonnet 5.5 vs GPT-6.1 Terra.