Solar Pro 4 vs Seed 2.1 Turbo
Too close to call on our weighted score (Seed 2.1 Turbo 57, Solar Pro 4 55). The right pick depends on what you value most.
Upstage
Solar Pro 4
55/100- ECI—
- Price$0.30 / $1.20
- Context524K
ByteDance SeedSeed 2.1 Turbo
57/100- ECI—
- Price$0.445 / $2.23
- Context256K
Add a model
Make it a three-way comparison.
Too close to call
It is close. Our weighted score puts them within 3 points (Seed 2.1 Turbo 57/100, Solar Pro 4 55/100), so choose by what matters most for your work: Solar Pro 4 on price and Solar Pro 4 for long inputs. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
- CapabilityNot enough dataNo independent benchmark covers every model here yet
- Lowest priceSolar Pro 4Solar Pro 4 $0.525 · Seed 2.1 Turbo $0.891 per 1M tokens (3:1 blend)
- Longest contextSolar Pro 4Solar Pro 4 524,288 · Seed 2.1 Turbo 256,000 tokens
- Widest inputsSeed 2.1 TurboSolar Pro 4: Text · Seed 2.1 Turbo: Text, Images, Video
- Self-hostingNo open weightsBoth are available only through APIs
| Measure | Weight | Solar Pro 4 | Seed 2.1 Turbo |
|---|---|---|---|
| Price | 50% | 63 | 52 |
| Inputs & features | 30% | 45 | 80 |
| Context window | 20% | 49 | 36 |
| Overall | 100% | 55/100 | 57/100 |
Left out because at least one model lacks the data: capability. The remaining weights were rescaled.
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | Solar Pro 4Upstage | Seed 2.1 TurboByteDance Seed |
|---|---|---|
| Capability | ||
| Capabilities Index (ECI) | — | — |
| ECI rank | — | — |
| Price per million tokens | ||
| Input | $0.30 (best) | $0.445 |
| Output | $1.20 (best) | $2.23 |
| Cached input | $0.06 (best) | $0.089 |
| Blended (3:1) | $0.525 (best) | $0.891 |
| Long-context rate | Same rate | Same rate |
| Price source | Official Upstage API | Official Volcengine Ark API |
| Limits | ||
| Context window | 524,288 tokens (best) | 256,000 tokens |
| Max output | 131,072 tokens | 256,000 tokens (best) |
| Inputs and features | ||
| Text | Yes | Yes |
| Images | No | Yes |
| PDFs | No | No |
| Audio | No | No |
| Video | No | Yes |
| Reasoning | Yesminimal · low · medium · high · xhigh · max | Yesminimal · low · medium · high · xhigh · max |
| Tool calling | Yes | Yes |
| Structured output | Yes | Yes |
| Availability | ||
| Weights | Proprietary | Proprietary |
| API model ID | solar-pro4 | doubao-seed-2-1-turbo-260628 |
| API providers | 3 | 4 (best) |
| Released | Aug 6, 2026 | Jun 23, 2026 |
| Knowledge cutoff | Feb 2026 | — |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- Solar Pro 4$5.40
- Seed 2.1 Turbo$8.91
Which should you choose?
Which is better: Solar Pro 4 or Seed 2.1 Turbo?
It is close. Our weighted score puts them within 3 points (Seed 2.1 Turbo 57/100, Solar Pro 4 55/100), so choose by what matters most for your work: Solar Pro 4 on price and Solar Pro 4 for long inputs. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.
Which is cheaper, Solar Pro 4 or Seed 2.1 Turbo?
Solar Pro 4 is cheaper at $0.30 input / $1.20 output per million tokens (official Upstage API price). Seed 2.1 Turbo costs $0.445 input / $2.23 output per million tokens (official Volcengine Ark API price). At a typical mix of three input tokens to one output token, that is $0.525 per million tokens for Solar Pro 4 versus $0.891 for Seed 2.1 Turbo (1.7× as much).
Which scores higher on benchmarks?
There is no independent benchmark that covers both models yet. Solar Pro 4 has not been scored yet and Seed 2.1 Turbo has not been scored yet.
Which is better for coding?
There are no published SWE-bench Verified results for Solar Pro 4 and Seed 2.1 Turbo yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.
Which has the bigger context window?
Solar Pro 4 has the largest context window at 524,288 tokens, against 256,000 for Seed 2.1 Turbo. Maximum output per response: Solar Pro 4 up to 131,072, Seed 2.1 Turbo up to 256,000 tokens.
Which can read images, PDFs, audio or video?
Solar Pro 4 accepts text; Seed 2.1 Turbo accepts text, images and video. Seed 2.1 Turbo handles the widest range of inputs.
Are any of these open source?
No. Solar Pro 4 and Seed 2.1 Turbo are proprietary and only available through APIs and apps.
Which is newer?
Solar Pro 4 is the newest, released Aug 6, 2026. Seed 2.1 Turbo came out Jun 23, 2026. Knowledge cutoff: Solar Pro 4 Feb 2026.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.
