GPT-5.1 Codex High vs GPT-6.1 Terra
GPT-6.1 Terra leads the LLM Stats Score 47.5 to 29.0. GPT-6.1 Terra is 1.7x cheaper per token.
OpenAI · OpenAI · Updated for 2026
Which is better?
GPT-6.1 Terra leads the overall LLM Stats Score 47.5 to 29.0, ranking #36 overall.
On price, GPT-6.1 Terra is roughly 1.7x 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 GPT-5.1 Codex High
- you want predictable pricing at $1.25/M input and $10.00/M output
Choose GPT-6.1 Terra
- overall performance matters — it scores 47.5 and ranks #36 on LLM Stats
- your work emphasizes reasoning — it leads those capability indexes
- cost matters — it's about 1.7x 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.
Individual benchmarks
1 reported for GPT-5.1 Codex High · 8 for GPT-6.1 Terra
GPT-5.1 Codex High and GPT-6.1 Terradon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-5.1 Codex High ($1.25/1M tokens) is 1.3x more expensive than GPT-6.1 Terra ($1.00/1M tokens).
For output processing, GPT-5.1 Codex High ($10.00/1M tokens) is 2.0x more expensive than GPT-6.1 Terra ($5.00/1M tokens).
In conclusion, GPT-5.1 Codex High 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 GPT-5.1 Codex High's 400,000 tokens. Both models can generate responses up to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
Both GPT-5.1 Codex High and GPT-6.1 Terra support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-5.1 Codex High
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
GPT-5.1 Codex High was released on 2025-11-12, while GPT-6.1 Terra was released on 2026-10-26.
GPT-6.1 Terra is 12 months newer than GPT-5.1 Codex High.
Nov 12, 2025
11 months ago
Oct 26, 2026
5 days ago
11mo newerKnowledge Cutoff
When training data ends
GPT-6.1 Terra has a documented knowledge cutoff of 2026-06-01, while GPT-5.1 Codex High's cutoff date is not specified.
We can confirm GPT-6.1 Terra's training data extends to 2026-06-01, but cannot make a direct comparison without GPT-5.1 Codex High's cutoff date.
—
Jun 2026
Provider Availability
GPT-5.1 Codex High is available from OpenAI. GPT-6.1 Terra is available from OpenAI.
GPT-5.1 Codex High
GPT-6.1 Terra
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-5.1 Codex High and GPT-6.1 Terra side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-5.1 Codex High vs GPT-6.1 Terra.