DeepSeek: DeepSeek V3.1 Terminus (exacto) vs OpenAI: gpt-oss-20b (batch)

OpenAI: gpt-oss-20b (batch) comes out ahead on the data we track: 1 advantage and none for DeepSeek: DeepSeek V3.1 Terminus (exacto).

Key numbers

SpecDeepSeek: DeepSeek V3.1 Terminus (exacto)OpenAI: gpt-oss-20b (batch)
ProviderDeepSeekOpenAI
Input price (per 1M tokens)$0.21$0.02
Output price (per 1M tokens)$0.79$0.11
Blended price (3:1 input/output)$0.35$0.05
Cheaper than … of all models we track61%87%
Context window164K tokens (~246 pages)131K tokens (~197 pages)
Larger context than … of all models36%23%
Max output per responsen/a118K tokens (~88,500 words)
Input typestexttext
Output typestexttext
Free variantNoNo
Listed since2025-09-222025-08-05
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What it costs for real workloads

Monthly cost at list price for five common workloads. Token counts per unit are stated so you can scale them to your own traffic. A workload that does not fit a model's context window is marked rather than priced.

Workload (per month)DeepSeek: DeepSeek V3.1 Terminus (exacto)OpenAI: gpt-oss-20b (batch)Difference
Customer-support chatbot
50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens)
$31.55$4.04OpenAI: gpt-oss-20b (batch) saves $27.51
RAG search over documents
20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens)
$33.10$4.00OpenAI: gpt-oss-20b (batch) saves $29.10
Coding / tool-using agent
2,000 tasks — each a multi-step task with tool calls and file context (60,000 in / 6,000 out tokens)
$34.68$4.22OpenAI: gpt-oss-20b (batch) saves $30.46
Batch summarisation
10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens)
$21.54$2.59OpenAI: gpt-oss-20b (batch) saves $18.95
Long-document analysis
500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens)
$11.29$1.31OpenAI: gpt-oss-20b (batch) saves $9.98

Capabilities side by side

CapabilityDeepSeek: DeepSeek V3.1 Terminus (exacto)OpenAI: gpt-oss-20b (batch)What it lets you do
Tool / function calling✓ Yes✓ Yescall your APIs and run agent loops
Structured output (JSON schema)✓ Yes✓ Yesreturn JSON that validates against your schema
Reasoning / thinking mode✓ Yes✓ Yesspend extra tokens thinking before answering hard problems
Image input——read screenshots, charts and scanned pages
Audio input——take speech or audio directly
File / PDF input——accept documents without your own parsing step
Image output——generate images, not just text
Built-in web search——answer from live web results
Seed (reproducible sampling)✓ Yes✓ Yesrepeat a generation for tests and evals
Log-probabilities——read token confidence for classification and scoring

From each model's published parameters and input/output types. “—” means not advertised, not proven absent.

Price history

DateModelInput / 1MOutput / 1M
2026-09-23OpenAI: gpt-oss-20b (batch)$0.02$0.11

Which should you choose?

Choose DeepSeek: DeepSeek V3.1 Terminus (exacto) if…

No advantage on the data we track — pick it for provider preference or output quality on your own prompts.

Choose OpenAI: gpt-oss-20b (batch) if…

  • cost matters at scale — it is 87% cheaper on a typical 3:1 input/output mix ($4.04 vs $31.55 a month for 50,000 support chats)

Frequently asked questions

Is DeepSeek: DeepSeek V3.1 Terminus (exacto) better than OpenAI: gpt-oss-20b (batch)?

OpenAI: gpt-oss-20b (batch) comes out ahead on the data we track: 1 advantage and none for DeepSeek: DeepSeek V3.1 Terminus (exacto).

Which is cheaper, DeepSeek: DeepSeek V3.1 Terminus (exacto) or OpenAI: gpt-oss-20b (batch)?

OpenAI: gpt-oss-20b (batch) is cheaper: $0.05 vs $0.35 per 1M tokens at a typical 3:1 input/output mix, 87% less. For 50,000 support conversations a month that is $4.04 against $31.55.

How much do DeepSeek: DeepSeek V3.1 Terminus (exacto) and OpenAI: gpt-oss-20b (batch) cost per million tokens?

DeepSeek: DeepSeek V3.1 Terminus (exacto) costs $0.21 per 1M input tokens and $0.79 per 1M output tokens; OpenAI: gpt-oss-20b (batch) costs $0.02 input and $0.11 output. Output tokens are billed separately, so long answers shift the gap.

Which has the bigger context window, DeepSeek: DeepSeek V3.1 Terminus (exacto) or OpenAI: gpt-oss-20b (batch)?

DeepSeek: DeepSeek V3.1 Terminus (exacto): 164K tokens, about 246 pages, against 131K (about 197 pages) for OpenAI: gpt-oss-20b (batch).

Do DeepSeek: DeepSeek V3.1 Terminus (exacto) and OpenAI: gpt-oss-20b (batch) support function calling and JSON output?

Tool calling — DeepSeek: DeepSeek V3.1 Terminus (exacto): yes, OpenAI: gpt-oss-20b (batch): yes. JSON-schema structured output — DeepSeek: DeepSeek V3.1 Terminus (exacto): yes, OpenAI: gpt-oss-20b (batch): yes.

Can DeepSeek: DeepSeek V3.1 Terminus (exacto) or OpenAI: gpt-oss-20b (batch) read images?

Neither accepts image input — both are text-in models.

Is DeepSeek: DeepSeek V3.1 Terminus (exacto) or OpenAI: gpt-oss-20b (batch) free to use?

No free variant is listed for either; both are pay-per-token.

When were DeepSeek: DeepSeek V3.1 Terminus (exacto) and OpenAI: gpt-oss-20b (batch) released?

DeepSeek: DeepSeek V3.1 Terminus (exacto) was listed on 2025-09-22; OpenAI: gpt-oss-20b (batch) on 2025-08-05.

Has the price of DeepSeek: DeepSeek V3.1 Terminus (exacto) or OpenAI: gpt-oss-20b (batch) changed?

DeepSeek: DeepSeek V3.1 Terminus (exacto): price unchanged since we started tracking it on 2026-03-10. OpenAI: gpt-oss-20b (batch): input price cut 52% ($0.05 → $0.02/1M), output price cut 44% ($0.20 → $0.11/1M) on 2026-09-23.

About the two models

DeepSeek

DeepSeek: DeepSeek V3.1 Terminus (exacto)

DeepSeek-V3.1 Terminus is an update to [DeepSeek V3.1](/deepseek/deepseek-chat-v3.1) that maintains the model's original capabilities while addressing issues reported by users, including language consistency and agent capabilities, further optimizing the model's performance in coding and search agents. It is a large hybrid reasoning model (671B parameters, 37B active) that supports both thinking and non-thinking modes. It extends the DeepSeek-V3 base with a two-phase long-context training process, reaching up to 128K tokens, and uses FP8 microscaling for efficient inference. Users can control the reasoning behaviour with the `reasoning` `enabled` boolean. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#enable-reasoning-with-default-config) The model improves tool use, code generation, and reasoning efficiency, achieving performance comparable to DeepSeek-R1 on difficult benchmarks while responding more quickly. It supports structured tool calling, code agents, and search agents, making it suitable for research, coding, and agentic workflows.

Full DeepSeek: DeepSeek V3.1 Terminus (exacto) specs →

Compare DeepSeek: DeepSeek V3.1 Terminus (exacto) with other models

Compare OpenAI: gpt-oss-20b (batch) with other models

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