Choose DeepSeek: DeepSeek V3.1 Terminus if…
No advantage on the data we track — pick it for provider preference or output quality on your own prompts.
DeepSeek: DeepSeek V3.1 Terminus vs OpenAI: gpt-oss-20b (batch)
OpenAI: gpt-oss-20b (batch) comes out ahead on the data we track: 2 advantages and none for DeepSeek: DeepSeek V3.1 Terminus.
Key numbers
| Spec | DeepSeek: DeepSeek V3.1 Terminus | OpenAI: gpt-oss-20b (batch) |
|---|---|---|
| Provider | DeepSeek | OpenAI |
| Input price (per 1M tokens) | $0.27 | $0.02 |
| Output price (per 1M tokens) | $1.00 | $0.11 |
| Blended price (3:1 input/output) | $0.45 | $0.05 |
| Cheaper than … of all models we track | 55% | 87% |
| Context window | 164K tokens (~246 pages) | 131K tokens (~197 pages) |
| Larger context than … of all models | 36% | 23% |
| Max output per response | 147K tokens (~110,600 words) | 118K tokens (~88,500 words) |
| Input types | text | text |
| Output types | text | text |
| Free variant | No | No |
| Listed since | 2025-09-22 | 2025-08-05 |
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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 | OpenAI: gpt-oss-20b (batch) | Difference |
|---|---|---|---|
| Customer-support chatbot 50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens) | $40.25 | $4.04 | OpenAI: gpt-oss-20b (batch) saves $36.21 |
| RAG search over documents 20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens) | $42.40 | $4.00 | OpenAI: gpt-oss-20b (batch) saves $38.40 |
| 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) | $44.40 | $4.22 | OpenAI: gpt-oss-20b (batch) saves $40.18 |
| Batch summarisation 10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens) | $27.60 | $2.59 | OpenAI: gpt-oss-20b (batch) saves $25.01 |
| Long-document analysis 500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens) | $14.50 | $1.31 | OpenAI: gpt-oss-20b (batch) saves $13.19 |
Capabilities side by side
| Capability | DeepSeek: DeepSeek V3.1 Terminus | OpenAI: gpt-oss-20b (batch) | What it lets you do |
|---|---|---|---|
| Tool / function calling | ✓ Yes | ✓ Yes | call your APIs and run agent loops |
| Structured output (JSON schema) | ✓ Yes | ✓ Yes | return JSON that validates against your schema |
| Reasoning / thinking mode | ✓ Yes | ✓ Yes | spend 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 | repeat 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
- DeepSeek: DeepSeek V3.1 Terminus: input price cut 10% ($0.30 → $0.27/1M) on 2026-10-03 (5 price changes since 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.
| Date | Model | Input / 1M | Output / 1M |
|---|---|---|---|
| 2026-10-03 | DeepSeek: DeepSeek V3.1 Terminus | $0.27 | $1.00 |
| 2026-09-29 | DeepSeek: DeepSeek V3.1 Terminus | $0.30 | $1.00 |
| 2026-09-23 | OpenAI: gpt-oss-20b (batch) | $0.02 | $0.11 |
| 2026-08-18 | DeepSeek: DeepSeek V3.1 Terminus | $0.27 | $1.00 |
| 2026-08-12 | DeepSeek: DeepSeek V3.1 Terminus | $0.27 | $0.95 |
| 2026-08-06 | DeepSeek: DeepSeek V3.1 Terminus | $0.27 | $1.00 |
Which should you choose?
Choose OpenAI: gpt-oss-20b (batch) if…
- cost matters at scale — it is 90% cheaper on a typical 3:1 input/output mix ($4.04 vs $40.25 a month for 50,000 support chats)
- you need seed (reproducible sampling) — to repeat a generation for tests and evals; DeepSeek: DeepSeek V3.1 Terminus does not advertise it
Frequently asked questions
Is DeepSeek: DeepSeek V3.1 Terminus better than OpenAI: gpt-oss-20b (batch)?
OpenAI: gpt-oss-20b (batch) comes out ahead on the data we track: 2 advantages and none for DeepSeek: DeepSeek V3.1 Terminus.
Which is cheaper, DeepSeek: DeepSeek V3.1 Terminus or OpenAI: gpt-oss-20b (batch)?
OpenAI: gpt-oss-20b (batch) is cheaper: $0.05 vs $0.45 per 1M tokens at a typical 3:1 input/output mix, 90% less. For 50,000 support conversations a month that is $4.04 against $40.25.
How much do DeepSeek: DeepSeek V3.1 Terminus and OpenAI: gpt-oss-20b (batch) cost per million tokens?
DeepSeek: DeepSeek V3.1 Terminus costs $0.27 per 1M input tokens and $1.00 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 or OpenAI: gpt-oss-20b (batch)?
DeepSeek: DeepSeek V3.1 Terminus: 164K tokens, about 246 pages, against 131K (about 197 pages) for OpenAI: gpt-oss-20b (batch).
Do DeepSeek: DeepSeek V3.1 Terminus and OpenAI: gpt-oss-20b (batch) support function calling and JSON output?
Tool calling — DeepSeek: DeepSeek V3.1 Terminus: yes, OpenAI: gpt-oss-20b (batch): yes. JSON-schema structured output — DeepSeek: DeepSeek V3.1 Terminus: yes, OpenAI: gpt-oss-20b (batch): yes.
Can DeepSeek: DeepSeek V3.1 Terminus or OpenAI: gpt-oss-20b (batch) read images?
Neither accepts image input — both are text-in models.
Is DeepSeek: DeepSeek V3.1 Terminus or OpenAI: gpt-oss-20b (batch) free to use?
No free variant is listed for either; both are pay-per-token.
What is the maximum output length of DeepSeek: DeepSeek V3.1 Terminus and OpenAI: gpt-oss-20b (batch)?
DeepSeek: DeepSeek V3.1 Terminus can write up to 147K tokens (about 110,600 words) per response; OpenAI: gpt-oss-20b (batch) up to 118K (about 88,500 words).
When were DeepSeek: DeepSeek V3.1 Terminus and OpenAI: gpt-oss-20b (batch) released?
DeepSeek: DeepSeek V3.1 Terminus was listed on 2025-09-22; OpenAI: gpt-oss-20b (batch) on 2025-08-05.
Has the price of DeepSeek: DeepSeek V3.1 Terminus or OpenAI: gpt-oss-20b (batch) changed?
DeepSeek: DeepSeek V3.1 Terminus: input price cut 10% ($0.30 → $0.27/1M) on 2026-10-03 (5 price changes since 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 V3.1 Terminus
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...
Full DeepSeek: DeepSeek V3.1 Terminus specs →OpenAI: gpt-oss-20b (batch)
gpt-oss-20b is an open-weight 21B parameter model released by OpenAI under the Apache 2.0 license. It uses a Mixture-of-Experts (MoE) architecture with 3.6B active parameters per forward pass, optimized for...
Full OpenAI: gpt-oss-20b (batch) specs →