OpenAI: GPT-5.6 Terra vs SpaceXAI: Grok 4.3
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-11-07.
| OpenAI: GPT-5.6 Terra | SpaceXAI: Grok 4.3 | |
|---|---|---|
| Vendor | openai | x-ai |
| Quality Score | 100 | 100 |
| Benchmark Score | 93.0 | 58.6 |
| Input Price | $2.00/M | $1.25/M |
| Output Price | $12.00/M | $2.50/M |
| Context Window | 1,050,000 | 1,000,000 |
| Max Output | 128,000 | 900,000 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | - |
| Benchmark Scores | ||
| ai_index | 90.7 | 62.0 |
| ai_index_agentic | 78.2 | 39.8 |
| ai_index_coding | 100.0 | 69.7 |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, Grok 4.3 costs $1.88 and GPT-5.6 Terra costs $5.00, so Grok 4.3 is about 2.7 times cheaper for the same work.
Both take in a similar amount of text: 1,050,000 and 1,000,000 tokens, about 1,575 and 1,500 pages.
On our blended benchmark score GPT-5.6 Terra leads 93.0 to 58.6.
Across the 20 tasks where they differ, GPT-5.6 Terra scores higher on 18 (SQL Generation, Code Review, Code Refactoring and others), Grok 4.3 on 2 (Code Completion, Bulk Data Labeling).
GPT-5.6 Terra was released in July 2026 and Grok 4.3 in April 2026.
Pick GPT-5.6 Terra if you need benchmark performance or the stronger all-round task scores; pick Grok 4.3 if you need lower cost.
Costs use current list prices per million tokens; page counts assume about 0.75 words per token and 500 words per page.
Who wins by task?
| Task | OpenAI: GPT-5.6 Terra | SpaceXAI: Grok 4.3 |
|---|---|---|
| SQL Generation | 171 | 158 |
| Code Review | 168 | 155 |
| Code Completion | 119 | 120 |
| Code Refactoring | 165 | 155 |
| Bug Fixing | 181 | 164 |
| Unit Test Generation | 155 | 144 |
| Code Documentation | 141 | 139 |
| Regex Writing | 135 | 130 |
| CI/CD Pipelines | 145 | 136 |
| Frontend Component Design | 147 | 138 |
| Data Analysis | 171 | 153 |
| CSV / Spreadsheet Cleanup | 153 | 147 |
| ETL Scripting | 155 | 145 |
| JSON Extraction | 138 | 134 |
| Bulk Data Labeling | 123 | 124 |
| OCR / Document Parsing | 147 | 141 |
| Table Extraction from PDFs | 147 | 141 |
| Long-Document Summarization | 159 | 152 |
| Short-Form Summarization | 122 | 120 |
| Blog Post Writing | 140 | 134 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →