Model comparison

DeepSeek V3.1 vs Mistral Small 4

DeepSeek against Mistral, compared on context, price, and verified benchmark results.

Catalog record checked September 26, 2026Individual provider fields may changeEvidence confidence: High — see receipts below

DeepSeek

DeepSeek V3.1

Budget · Open weights

Mistral

Mistral Small 4

Budget · Open weights

AI model capability comparison
Specification	DeepSeek V3.1	Mistral Small 4
Provider
Provider	DeepSeek	Mistral
Tier
Tier	Budget	Budget
Context window
Context window	128K	Winner: 262K
Max output
Max output	Not verifiedUnverified	Not verifiedUnverified
Input / 1M tokens
Input / 1M tokens	$0.25	Winner: $0.15
Output / 1M tokens
Output / 1M tokens	$0.95	Winner: $0.60
Weights
Weights	Open	Open
Parameters
Parameters	671B total / 37B active (MoE)	119B total / 6.5B active (MoE)
Reasoning levels
Reasoning levels	low, high, max	Not verifiedUnverified
Modalities
Modalities	text	text, image
License
License	MIT	Apache 2.0
API model id
API model id	Not publishedUnverified	mistral-small-2603
Released
Released	August 21, 2025	March 16, 2026
Artificial Analysis Intelligence Index (2026-09-26)
Artificial Analysis Intelligence Index (2026-09-26)	Winner: 13.5	11.3

Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.

Benchmark receipts

Where each score comes from, and how far it can be compared across models.

2026-09-26
Artificial Analysis (Reasoning)
Composite index blending reasoning, knowledge, and coding evals into one 0–100 score.
Comparable with caveatOnly same-version scores are comparable. v4.3.2 was rebaselined (the top score fell from 66 on v4.1.1 to ~58), so v4.1.1 figures must not be compared with v4.3.2 figures — check measuredAt.

Pricing tiers

DeepSeek V3.1: No first-party API: DeepSeek moved the deepseek-chat alias to V3.1-Terminus on 2025-09-22 (the alias itself was retired on 2026-07-24). Third-party hosts listed ~$0.25/$0.95 per MTok (secondary, last checked 2026-08-29) — verify with your host.

Mistral Small 4: Mistral first-party API $0.15/$0.60 per MTok. Open weights (Apache 2.0). 119B total / 6.5B active MoE.

BudgetOpen weightsRecord checked September 26, 2026

DeepSeek V3.1

DeepSeek V3.1 is a legacy open-weight (MIT) 671B/37B MoE with a 128K context — superseded by V3.1-Terminus, V3.2 and then V4.

Best for

Cost-sensitive hosted agents
High-volume coding assist
Open-weight deployments

Watch out

Legacy: DeepSeek's own API stopped serving V3.1 when deepseek-chat moved to V3.1-Terminus on 2025-09-22; hosted rates differ by provider and self-hosting needs datacentre VRAM.

BudgetOpen weightsRecord checked September 26, 2026

Mistral Small 4

Mistral Small 4 is Mistral's low-cost Apache-2.0 MoE — 6.5B active parameters with a 256K context and image input.

Best for

Cheap EU-hosted inference
Open-weight self-hosting
High-volume extraction

Watch out

Small active size: not for hard reasoning or agentic coding; max output is not published.

When the cheaper one wins

Mistral Small 4 is cheaper on output at $0.60 per million tokens against $0.95 for DeepSeek V3.1 — about 1.6×. Use the cheaper tier for classification, extraction, summarisation, and any task where the expensive model’s extra score does not change the accepted output. The expensive one only pays if your hardest task actually fails on the cheap tier. These are standard-tier API rates, excluding batch and cache discounts.

Run the model picker

Evidence confidence: High

How strong and complete the evidence behind this comparison is — not a prediction of which model is better.

Pricing verified on both sides — Input and output rates are verified for both models.
3/5 core specs verified on both sides — Not published for at least one side: max output, reasoning levels.
1 shared named benchmark with differing scores — Measured on: Artificial Analysis Intelligence Index.
Verified within the last 90 days — Newest catalog check was 2 days ago.
Both models carry source citations — Each side has at least two catalog sources on record.

Source receipts

Each catalog figure was checked against the provider or an independent second source on the date shown.

DeepSeek V3.1: DeepSeek — V3.1 (accessed 2026-08-29)
DeepSeek V3.1: CloudPrice — DeepSeek V3.1 (accessed 2026-08-29)
DeepSeek V3.1: DeepSeek API changelog (2025-09-22: deepseek-chat upgraded to V3.1-Terminus) (accessed 2026-09-26)
Mistral Small 4: Mistral docs — Mistral Small 4 (26.03) (accessed 2026-09-26)
Mistral Small 4: Mistral changelog (accessed 2026-09-26)

Related comparisons

Diving deeper on one model? DeepSeek V3.1 · Mistral Small 4

Common questions

DeepSeek V3.1 vs Mistral Small 4

Answered from the verified figures on this page rather than general guidance.

Is DeepSeek V3.1 or Mistral Small 4 cheaper for input?

Mistral Small 4 is cheaper at $0.15 per million input tokens, against $0.25 for DeepSeek V3.1 — roughly 1.7× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; DeepSeek V3.1 has tiered pricing: No first-party API: DeepSeek moved the deepseek-chat alias to V3.1-Terminus on 2025-09-22 (the alias itself was retired on 2026-07-24). Third-party hosts listed ~$0.25/$0.95 per MTok (secondary, last checked 2026-08-29) — verify with your host. Mistral Small 4 has tiered pricing: Mistral first-party API $0.15/$0.60 per MTok. Open weights (Apache 2.0). 119B total / 6.5B active MoE.

Is DeepSeek V3.1 or Mistral Small 4 cheaper for output?

Mistral Small 4 is cheaper at $0.60 per million output tokens, against $0.95 for DeepSeek V3.1 — roughly 1.6× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; DeepSeek V3.1 has tiered pricing: No first-party API: DeepSeek moved the deepseek-chat alias to V3.1-Terminus on 2025-09-22 (the alias itself was retired on 2026-07-24). Third-party hosts listed ~$0.25/$0.95 per MTok (secondary, last checked 2026-08-29) — verify with your host. Mistral Small 4 has tiered pricing: Mistral first-party API $0.15/$0.60 per MTok. Open weights (Apache 2.0). 119B total / 6.5B active MoE.

Which has the larger context window, DeepSeek V3.1 or Mistral Small 4?

Mistral Small 4 accepts 262K tokens against 128K for DeepSeek V3.1. This only matters if you routinely send very long documents or large codebases.

Should I use DeepSeek V3.1 or Mistral Small 4?

Both sit in the budget tier, so the choice usually comes down to price and context rather than capability. DeepSeek V3.1 suits cost-sensitive hosted agents; Mistral Small 4 suits cheap eu-hosted inference.

Next step

Choosing between them

The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.

Input price: Mistral Small 4 costs $0.15 per 1M tokens versus $0.25 for DeepSeek V3.1 — a 1.7x difference at the headline tier.
Context: Mistral Small 4 takes 262K against 128K for DeepSeek V3.1 — only decisive if your prompts approach the smaller window.

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