ByteDance Seed: Seed-2.0-Code vs OpenAI: GPT-5.6 Luna
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-09-27.
| ByteDance Seed: Seed-2.0-Code | OpenAI: GPT-5.6 Luna | |
|---|---|---|
| Vendor | bytedance-seed | openai |
| Quality Score | 100 | 100 |
| Benchmark Score | - | 62.3 |
| Input Price | $0.50/M | $0.20/M |
| Output Price | $3.00/M | $1.20/M |
| Context Window | 262,144 | 1,050,000 |
| Max Output | 131,072 | 128,000 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | - |
| Benchmark Scores | ||
| ai_index | - | 61.6 |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, GPT-5.6 Luna costs $0.50 and Seed-2.0-Code costs $1.25, so GPT-5.6 Luna is about 2.5 times cheaper for the same work.
GPT-5.6 Luna reads up to 1,050,000 tokens at once, roughly 1,575 pages of text, against about 393 pages for Seed-2.0-Code.
Only Seed-2.0-Code offers video input.
Across the 20 tasks where they differ, GPT-5.6 Luna on 20 (SQL Generation, Code Review, Code Completion and others).
Seed-2.0-Code was released in August 2026 and GPT-5.6 Luna in July 2026.
Pick Seed-2.0-Code if you need video input; pick GPT-5.6 Luna if you need lower cost, 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-2.0-Code | OpenAI: GPT-5.6 Luna |
|---|---|---|
| SQL Generation | 130 | 141 |
| Code Review | 126 | 143 |
| Code Completion | 128 | 133 |
| Code Refactoring | 127 | 145 |
| Bug Fixing | 130 | 147 |
| Unit Test Generation | 121 | 131 |
| Code Documentation | 125 | 137 |
| Regex Writing | 119 | 125 |
| CI/CD Pipelines | 117 | 127 |
| Frontend Component Design | 122 | 129 |
| Data Analysis | 124 | 133 |
| CSV / Spreadsheet Cleanup | 128 | 136 |
| ETL Scripting | 122 | 136 |
| JSON Extraction | 131 | 131 |
| Bulk Data Labeling | 128 | 129 |
| OCR / Document Parsing | 128 | 134 |
| Table Extraction from PDFs | 128 | 134 |
| Long-Document Summarization | 129 | 147 |
| Short-Form Summarization | 123 | 126 |
| Blog Post Writing | 118 | 129 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →