ByteDance Seed: Seed 2.1 Turbo vs OpenAI: GPT-5.6 Terra Pro
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-09-27.
| ByteDance Seed: Seed 2.1 Turbo | OpenAI: GPT-5.6 Terra Pro | |
|---|---|---|
| Vendor | bytedance-seed | openai |
| Quality Score | 100 | 100 |
| Input Price | $0.50/M | $2.00/M |
| Output Price | $2.50/M | $12.00/M |
| Context Window | 262,144 | 1,050,000 |
| Max Output | 235,929 | 128,000 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | - |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, Seed 2.1 Turbo costs $1.12 and GPT-5.6 Terra Pro costs $5.00, so Seed 2.1 Turbo is about 4.4 times cheaper for the same work.
GPT-5.6 Terra Pro reads up to 1,050,000 tokens at once, roughly 1,575 pages of text, against about 393 pages for Seed 2.1 Turbo.
Only Seed 2.1 Turbo offers video input.
Across the 18 tasks where they differ, Seed 2.1 Turbo scores higher on 5 (Code Completion, Regex Writing, JSON Extraction and others), GPT-5.6 Terra Pro on 13 (SQL Generation, Code Review, Code Refactoring and others).
Seed 2.1 Turbo was released in August 2026 and GPT-5.6 Terra Pro in July 2026.
Pick Seed 2.1 Turbo if you need lower cost or video input; pick GPT-5.6 Terra Pro if you need long documents or the stronger all-round task scores.
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 | ByteDance Seed: Seed 2.1 Turbo | OpenAI: GPT-5.6 Terra Pro |
|---|---|---|
| SQL Generation | 130 | 132 |
| Code Review | 126 | 132 |
| Code Completion | 128 | 117 |
| Code Refactoring | 127 | 136 |
| Bug Fixing | 130 | 136 |
| Unit Test Generation | 121 | 124 |
| Code Documentation | 125 | 129 |
| Regex Writing | 119 | 117 |
| CI/CD Pipelines | 117 | 120 |
| CSV / Spreadsheet Cleanup | 128 | 132 |
| ETL Scripting | 122 | 128 |
| JSON Extraction | 131 | 121 |
| Bulk Data Labeling | 129 | 117 |
| OCR / Document Parsing | 128 | 131 |
| Table Extraction from PDFs | 128 | 131 |
| Long-Document Summarization | 129 | 136 |
| Short-Form Summarization | 123 | 113 |
| Blog Post Writing | 118 | 120 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →