ByteDance Seed: Seed 2.1 Turbo vs StepFun: Step 3.7 Flash
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-11-12.
| ByteDance Seed: Seed 2.1 Turbo | StepFun: Step 3.7 Flash | |
|---|---|---|
| Vendor | bytedance-seed | stepfun |
| Quality Score | 100 | 100 |
| Input Price | $0.50/M | $0.20/M |
| Output Price | $2.50/M | $1.15/M |
| Context Window | 262,144 | 262,144 |
| Max Output | 235,929 | 230,400 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | - |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, Step 3.7 Flash costs $0.49 and Seed 2.1 Turbo costs $1.12, so Step 3.7 Flash is about 2.3 times cheaper for the same work.
Both read up to 262,144 tokens at once, roughly 393 pages of text.
Across the 10 tasks where they differ, Step 3.7 Flash on 10 (SQL Generation, Code Completion, Code Documentation and others).
Seed 2.1 Turbo was released in August 2026 and Step 3.7 Flash in May 2026.
Pick Step 3.7 Flash if you need lower cost 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 | StepFun: Step 3.7 Flash |
|---|---|---|
| SQL Generation | 130 | 131 |
| Code Completion | 128 | 129 |
| Code Documentation | 125 | 126 |
| Regex Writing | 119 | 119 |
| CSV / Spreadsheet Cleanup | 128 | 128 |
| JSON Extraction | 131 | 131 |
| Bulk Data Labeling | 129 | 129 |
| Long-Document Summarization | 129 | 129 |
| Short-Form Summarization | 123 | 123 |
| Blog Post Writing | 118 | 119 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →