Neither wins outright: DeepSeek: DeepSeek V4 Flash 0731 is the pick when you need seed (reproducible sampling), Inception: Mercury 3 when cost matters at scale.
| Spec | DeepSeek: DeepSeek V4 Flash 0731 | Inception: Mercury 3 |
|---|---|---|
| Provider | DeepSeek | Inception |
| Input price (per 1M tokens) | $0.44 | $0.10 |
| Output price (per 1M tokens) | $1.32 | $0.35 |
| Blended price (3:1 input/output) | $0.66 | $0.16 |
| Cheaper than … of all models we track | 48% | 73% |
| Context window | 1.0M tokens (~1,573 pages) | 1M tokens (~1,500 pages) |
| Larger context than … of all models | 81% | 69% |
| Max output per response | 131K tokens (~98,300 words) | 131K tokens (~98,300 words) |
| Input types | text | text |
| Output types | text | text |
| Free variant | Yes | No |
| Listed since | 2026-07-31 | 2026-10-16 |
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 V4 Flash 0731 | Inception: Mercury 3 | Difference |
|---|---|---|---|
| Customer-support chatbot 50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens) | $59.40 | $14.50 | Inception: Mercury 3 saves $44.90 |
| RAG search over documents 20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens) | $66.00 | $15.50 | Inception: Mercury 3 saves $50.50 |
| 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) | $68.64 | $16.20 | Inception: Mercury 3 saves $52.44 |
| Batch summarisation 10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens) | $43.12 | $10.10 | Inception: Mercury 3 saves $33.02 |
| Long-document analysis 500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens) | $23.32 | $5.35 | Inception: Mercury 3 saves $17.97 |
| Capability | DeepSeek: DeepSeek V4 Flash 0731 | Inception: Mercury 3 | 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 | ✓ Yes | — | read token confidence for classification and scoring |
From each model's published parameters and input/output types. “—” means not advertised, not proven absent.
| Date | Model | Input / 1M | Output / 1M |
|---|---|---|---|
| 2026-10-20 | DeepSeek: DeepSeek V4 Flash 0731 | $0.44 | $1.32 |
| 2026-10-19 | DeepSeek: DeepSeek V4 Flash 0731 | $0.15 | $0.15 |
| 2026-10-18 | DeepSeek: DeepSeek V4 Flash 0731 | $0.10 | $0.30 |
| 2026-10-17 | DeepSeek: DeepSeek V4 Flash 0731 | $0.07 | $0.14 |
| 2026-10-16 | DeepSeek: DeepSeek V4 Flash 0731 | $0.0049 | $0.64 |
| 2026-10-13 | DeepSeek: DeepSeek V4 Flash 0731 | $0.02 | $0.64 |
| 2026-10-12 | DeepSeek: DeepSeek V4 Flash 0731 | $0.0079 | $0.64 |
| 2026-10-11 | DeepSeek: DeepSeek V4 Flash 0731 | $0.01 | $1.28 |
Neither wins outright: DeepSeek: DeepSeek V4 Flash 0731 is the pick when you need seed (reproducible sampling), Inception: Mercury 3 when cost matters at scale. In short: DeepSeek: DeepSeek V4 Flash 0731 when you need seed (reproducible sampling), you need log-probabilities, you want to prototype at zero cost; Inception: Mercury 3 when cost matters at scale.
Inception: Mercury 3 is cheaper: $0.16 vs $0.66 per 1M tokens at a typical 3:1 input/output mix, 75% less. For 50,000 support conversations a month that is $14.50 against $59.40.
DeepSeek: DeepSeek V4 Flash 0731 costs $0.44 per 1M input tokens and $1.32 per 1M output tokens; Inception: Mercury 3 costs $0.10 input and $0.35 output. Output tokens are billed separately, so long answers shift the gap.
DeepSeek: DeepSeek V4 Flash 0731: 1.0M tokens, about 1,573 pages, against 1M (about 1,500 pages) for Inception: Mercury 3.
Tool calling — DeepSeek: DeepSeek V4 Flash 0731: yes, Inception: Mercury 3: yes. JSON-schema structured output — DeepSeek: DeepSeek V4 Flash 0731: yes, Inception: Mercury 3: yes.
Neither accepts image input — both are text-in models.
DeepSeek: DeepSeek V4 Flash 0731 has a free variant (deepseek/deepseek-v4-flash-0731:free). Free variants usually carry tighter rate limits.
DeepSeek: DeepSeek V4 Flash 0731 can write up to 131K tokens (about 98,300 words) per response; Inception: Mercury 3 up to 131K (about 98,300 words).
DeepSeek: DeepSeek V4 Flash 0731 was listed on 2026-07-31; Inception: Mercury 3 on 2026-10-16.
DeepSeek: DeepSeek V4 Flash 0731: input price raised 66% ($0.15 → $0.44/1M), output price raised 89% ($0.15 → $1.32/1M) on 2026-10-20 (39 price changes since 2026-08-06). Inception: Mercury 3: price unchanged since we started tracking it on 2026-10-20.
DeepSeek V4 Flash 0731 is a sparse mixture-of-experts model from DeepSeek, with 13B active parameters out of 284B total. This re-post-trained revision is suited for coding, reasoning, and agent workflows....
Full DeepSeek: DeepSeek V4 Flash 0731 specs →Mercury 3 is a diffusion-based language model from Inception, and the lab's most capable model to date. It is suited for agentic workflows and real-time applications where latency compounds, such...
Full Inception: Mercury 3 specs →