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GPT-6.1 Terra vs Grok-1.5

GPT-6.1 Terra leads the LLM Stats Score 47.5 to -3.1.

OpenAI · xAI · Updated for 2026

Which is better?

GPT-6.1 Terra leads the overall LLM Stats Score 47.5 to -3.1, ranking #36 overall.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose GPT-6.1 Terra

  • overall performance matters — it scores 47.5 and ranks #36 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you want the most recent training data — it shipped Oct 2026

Choose Grok-1.5

  • you are already invested in the xAI ecosystem

At a glance

The differences that matter most.

GPT-6.1 Terra
OpenAI
Grok-1.5
xAI
Core performance indexes
LLM Stats Score
47.5
#36
-3.1
#377
Reasoning
49.0
#19
-2.6
#367
Coding
37.1
#30
-1.0
#280
Cost, coverage & limits
Benchmark wins
—
—
Input price
$1.00 / M
— / M
Output price
$5.00 / M
— / M
Context window
1,050,000
—

Individual benchmarks

8 reported for GPT-6.1 Terra · 9 for Grok-1.5

No common benchmarks found

GPT-6.1 Terra and Grok-1.5don'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

Context Window

Maximum input and output token capacity

Only GPT-6.1 Terra specifies input context (1,050,000 tokens). Only GPT-6.1 Terra specifies output context (128,000 tokens).

OpenAI
GPT-6.1 Terra
Input1,050,000 tokens
Output128,000 tokens
xAI
Grok-1.5
Input- tokens
Output- tokens
Fri Oct 30 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

GPT-6.1 Terra supports multimodal inputs, whereas Grok-1.5 does not.

GPT-6.1 Terra can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-6.1 Terra

Text
Images
Audio
Video

Grok-1.5

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

GPT-6.1 Terra

Proprietary

Closed source

Grok-1.5

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-6.1 Terra was released on 2026-10-26, while Grok-1.5 was released on 2024-03-28.

GPT-6.1 Terra is 31 months newer than Grok-1.5.

GPT-6.1 Terra

Oct 26, 2026

0 days ago

2.6yr newer
Grok-1.5

Mar 28, 2024

2.6 years ago

Knowledge Cutoff

When training data ends

GPT-6.1 Terra has a documented knowledge cutoff of 2026-06-01, while Grok-1.5'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 Grok-1.5's cutoff date.

GPT-6.1 Terra

Jun 2026

Grok-1.5

—

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against GPT-6.1 Terra and Grok-1.5 side-by-side, then vote on the output you prefer.

GPT-6.1 Terra
✓ Preferred
Grok-1.5
Open in Playground

FAQ

Common questions about GPT-6.1 Terra vs Grok-1.5.

Which is better, GPT-6.1 Terra or Grok-1.5?

GPT-6.1 Terra leads the LLM Stats Score 47.5 to -3.1. GPT-6.1 Terra is made by OpenAI and Grok-1.5 is made by xAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does GPT-6.1 Terra compare to Grok-1.5 in benchmarks?

GPT-6.1 Terra scores HealthBench Consensus: 95.1%, HealthBench Professional: 62.7%, Agents' Last Exam: 60.0%, Terminal-Bench-Science 0.1: 58.3%, MentalHealthBench: 55.5%. Grok-1.5 scores GSM8k: 90.0%, DocVQA: 85.6%, MMLU: 81.3%, HumanEval: 74.1%, MMMU: 53.6%.

What are the context window sizes for GPT-6.1 Terra and Grok-1.5?

GPT-6.1 Terra supports 1.1M tokens and Grok-1.5 supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-6.1 Terra and Grok-1.5?

Key differences include LLM Stats Score (47.5 vs -3.1), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-6.1 Terra and Grok-1.5?

GPT-6.1 Terra is developed by OpenAI and Grok-1.5 is developed by xAI.

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