Doubao Seed Evolving vs GPT-5.6 Terra
Doubao Seed Evolving wins on Overall, Multimodal; GPT-5.6 Terra wins on Coding. Every numeric field is compared below, with a worked monthly-cost example and a pick rule for each use case.
Verdict at a glance
Choose Doubao Seed Evolving if you…
- Continuously updated
- 1M context
- Good Chinese
- ByteDance ecosystem
- Best for: Chinese, Long context, Continuously evolving
Choose GPT-5.6 Terra if you…
- OpenAI quality
- Halved price
- Rich ecosystem
- Best for: Value, General tasks, OpenAI ecosystem
Head-to-head aggregate scores
Scores are 0–100, aggregated from public benchmark information and independently weighted across three leaderboards. Rank is out of 22 tracked models.
Aggregated from public sources and independently weighted; methodology on the Terms page. Scores within 3 points are treated as statistically tied.
Specs & pricing — every field side by side
List API prices in USD per 1M tokens. The highlighted cell is the stronger value/capability on that row.
| Dimension | Doubao Seed Evolving | GPT-5.6 Terra | Verdict |
|---|---|---|---|
| Vendor | ByteDance (CN) | OpenAI (US) | Different vendors |
| Released | 2026.07 | 2026.07 | GPT-5.6 Terra is newer |
| Overall (rank) | 68 · #15 | 62 · #21 | Doubao Seed Evolving +6 |
| Coding | 67 · #14 | 70 · #12 | GPT-5.6 Terra +3 |
| Multimodal | 83 · #9 | 69 · #19 | Doubao Seed Evolving +14 |
| Context window | 1M | 1.05M | GPT-5.6 Terra larger |
| Max output | 256K | 128K | Doubao Seed Evolving longer |
| Effective-context | 92 | 88 | Doubao Seed Evolving more reliable |
| Input $/1M | $0.83 | $2.5 | Doubao Seed Evolving cheaper |
| Output $/1M | $4.17 | $15 | Doubao Seed Evolving cheaper |
| Cache discount | custom | 50% off | GPT-5.6 Terra deeper |
| Speed | ~60 tok/s | ~60 tok/s | Tie |
| TTFT | 0.5s | 0.5s | Tie |
| Function calling | 82 | 90 | GPT-5.6 Terra ahead |
| Refusal rate | ~10% | ~13% | Doubao Seed Evolving less restrictive |
| English | 70 | 88 | GPT-5.6 Terra |
| Chinese | 93 | 72 | Doubao Seed Evolving |
| Modalities | text, image | text, image | Same |
| Open weights | No | No | Both closed |
| Fine-tuning | No | No | |
| Free tier | Doubao App free | No free API | |
| SOC2 / no-train | no / yes | yes / yes | |
| Private deployment | Yes | No | Doubao Seed Evolving |
Fields drawn from vendor public documentation and the Modelspectra 22-model dataset; speed varies with network, concurrency and prompt length. Verify current pricing before purchase.
Dimension-by-dimension analysis
Reasoning & overall intelligence
Doubao Seed Evolving leads the overall aggregate by 6 points (68 vs 62). That is a meaningful, not marginal, edge on hard, multi-step reasoning, while GPT-5.6 Terra remains a strong generalist that is not out of its depth on routine work.
Agentic coding
This is a modest gap: GPT-5.6 Terra scores 70 against 67. On multi-file edits, SWE-style tickets and long-horizon agent loops GPT-5.6 Terra needs fewer correction turns; Doubao Seed Evolving is still competent for scripts and assisted completion but trails as task complexity rises.
Multimodal
Doubao Seed Evolving leads multimodal 83 vs 69. Neither emits native video, so the comparison is about parsing images and documents, not generation.
Speed & latency
Doubao Seed Evolving is faster in interactive use: ~60 tok/s with 0.5s TTFT versus ~60 tok/s with 0.5s TTFT (about 1.0× the throughput). For conversational UIs where perceived responsiveness drives retention, that edge is a real product factor even when raw reasoning is lower.
Context: window vs usable recall
Nominal windows are 1M for Doubao Seed Evolving and 1.05M for GPT-5.6 Terra. Crucially, the larger nominal window does not win on usable recall: GPT-5.6 Terra advertises 1.05M but Doubao Seed Evolving scores higher on effective-context (92 vs 88), i.e. it actually retains more of what it was given.
Price & total cost
Doubao Seed Evolving is the cheaper API at $0.83/$4.17 versus GPT-5.6 Terra at $2.5/$15 per 1M input/output tokens — list input is about 3.0× lower. Cache discounts (GPT-5.6 Terra 50%) shift the effective bill, worked out below.
Chinese vs English
English: Doubao Seed Evolving 70 vs GPT-5.6 Terra 88. Chinese: 93 vs 72. For Chinese-language production, Doubao Seed Evolving is the stronger pick. Note that non-Chinese models generally require overseas network access for their APIs.
Tool use & ecosystem
Function-calling score: Doubao Seed Evolving 82 vs GPT-5.6 Terra 90, so GPT-5.6 Terra has the edge on structured tool use. Neither offers standard fine-tuning. Factor in existing SDK/plugin familiarity — switching cost often outweighs a few-point tool-use gap.
Cost worked example — same workload, real token math
Assume a production workload of 100M input + 30M output tokens per month, with 90% of input tokens served from cache. Figures use public list prices.
| Scenario · per month | Doubao Seed Evolving | GPT-5.6 Terra | Gap |
|---|---|---|---|
| List priceno cache applied | $208100M in × $0.83 + 30M out × $4.17 | $700100M in × $2.5 + 30M out × $15 | 3.37×gap |
| With caching90% of inputs cache-hit | $208no published cache discount | $58890M cached in × $1.25 + 10M in × $2.5 + 30M out × $15 | 2.83×gap |
Illustrative model; your input/output mix and cache-hit ratio change the result. Prices are list rates before any enterprise agreement.