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AI Choice Engine

Model comparison

DeepSeek V4.1 Flash vs DeepSeek V4 Pro

Two DeepSeek tiers compared on the figures that decide which one a workload actually needs.

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

DeepSeek

DeepSeek V4.1 Flash

Balanced · Open weights

vs

DeepSeek

DeepSeek V4 Pro

Frontier · Open weights

AI model capability comparison
SpecificationDeepSeek V4.1 FlashDeepSeek V4 Pro
ProviderDeepSeekDeepSeek
TierBalancedFrontier
Context window1M1M
Max output384K384K
Input / 1M tokensWinner: $0.30$1.32
Output / 1M tokensWinner: $1.20$3.96
WeightsOpenOpen
Parameters552B MoE (causal encoder-decoder; 8B active for input, 16B for output)1.6T total / 49B active (MoE)
Reasoning levelslow, high, maxlow, high, max
Modalitiestext, imagetext
LicenseMITMIT
API model iddeepseek-flashdeepseek-v4-pro
ReleasedSeptember 10, 2026April 24, 2026
Artificial Analysis Intelligence Index [max] (2026-09-26)Winner: 39.536
DeepSWE 1.1 [max] (2026-09-10)74.2Not verifiedUnverified
Terminal-Bench 2.1 [max] (2026-09-10)90.6Not verifiedUnverified
GPQA Diamond [max] (2026-09-10)90.9Not verifiedUnverified
GPQA Diamond (2026-04-24)Not verifiedUnverified90.1
SWE-bench Verified (2026-04-24)Not verifiedUnverified80.6
Humanity's Last Exam (2026-04-24)Not verifiedUnverified48.2
MMLU-Pro (2026-04-24)Not verifiedUnverified87.5

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 (0813 GA checkpoint)

    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.

  • 2026-09-10
    DeepSeek V4.1-Flash release notes (vendor)

    Agentic software engineering: pass@1 on real repo tasks with reported cost per completed task.

    Directly comparable

  • 2026-04-24
    DeepSeek V4 Pro HF model card (vendor, Think Max, exact match)

    Real GitHub issue resolution: does the model's patch pass the hidden tests.

    Comparable with caveatPost-audit vendor claims and pre-audit scores sit on different task trust levels; scaffolding (agent harness, compute budget) also dominates results. Never aggregate across scaffolds.

Pricing tiers

DeepSeek V4.1 Flash: Official peak rates $0.30/$1.20 per MTok; off-peak $0.15/$0.60 (50% of peak). Cache hit $0.006 peak / $0.003 off-peak. Peak hours are weekdays 01:00–04:00 and 06:00–10:00 UTC. Open weights (MIT). The legacy deepseek-v4-flash and deepseek-v4-flash-vision-exp ids temporarily route here.

DeepSeek V4 Pro: Official peak rates $1.32/$3.96 per MTok; off-peak $0.66/$1.98 (cache-miss). Cache hit $0.044 peak / $0.022 off-peak. Peak hours are weekdays 01:00–04:00 and 06:00–10:00 UTC. Open weights (MIT). 1.6T/49B active MoE.

BalancedOpen weightsRecord checked September 26, 2026

DeepSeek V4.1 Flash

DeepSeek V4.1 Flash is DeepSeek's new default — an open-weight (MIT) multimodal MoE that DeepSeek says beats V4-Pro on performance, cost and speed.

Best for

  • Open-weight price-performance
  • High-volume hosted agents
  • Self-hosting with MIT weights

Watch out

Vendor benchmark claims are far ahead of its independent Artificial Analysis score (39.5 on v4.3.2); peak/off-peak billing means the hour you run matters.

FrontierOpen weightsRecord checked September 26, 2026

DeepSeek V4 Pro

DeepSeek V4 Pro is DeepSeek's large open-weight (MIT) MoE with a 1M-token context — DeepSeek says the cheaper V4.1-Flash now beats it.

Best for

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

Watch out

On 2026-09-10 DeepSeek said it is phasing out V4-Pro (it later reversed the 2026-09-14 re-route and still serves it); plan new work on V4.1-Flash. Self-hosting needs datacentre VRAM.

When the cheaper one wins

DeepSeek V4.1 Flash is cheaper on output at $1.20 per million tokens against $3.96 for DeepSeek V4 Pro — about 3.3×. 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.
  • 5/5 core specs verified on both sides — All core specifications verified for both models.
  • 2 shared named benchmarks with differing scores — Measured on: Artificial Analysis Intelligence Index, GPQA Diamond.
  • 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.

Related comparisons

Diving deeper on one model? DeepSeek V4.1 Flash · DeepSeek V4 Pro

Common questions

DeepSeek V4.1 Flash vs DeepSeek V4 Pro

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

Is DeepSeek V4.1 Flash or DeepSeek V4 Pro cheaper for input?
DeepSeek V4.1 Flash is cheaper at $0.30 per million input tokens, against $1.32 for DeepSeek V4 Pro — roughly 4.4× 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 V4.1 Flash has tiered pricing: Official peak rates $0.30/$1.20 per MTok; off-peak $0.15/$0.60 (50% of peak). Cache hit $0.006 peak / $0.003 off-peak. Peak hours are weekdays 01:00–04:00 and 06:00–10:00 UTC. Open weights (MIT). The legacy deepseek-v4-flash and deepseek-v4-flash-vision-exp ids temporarily route here. DeepSeek V4 Pro has tiered pricing: Official peak rates $1.32/$3.96 per MTok; off-peak $0.66/$1.98 (cache-miss). Cache hit $0.044 peak / $0.022 off-peak. Peak hours are weekdays 01:00–04:00 and 06:00–10:00 UTC. Open weights (MIT). 1.6T/49B active MoE.
Is DeepSeek V4.1 Flash or DeepSeek V4 Pro cheaper for output?
DeepSeek V4.1 Flash is cheaper at $1.20 per million output tokens, against $3.96 for DeepSeek V4 Pro — roughly 3.3× 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 V4.1 Flash has tiered pricing: Official peak rates $0.30/$1.20 per MTok; off-peak $0.15/$0.60 (50% of peak). Cache hit $0.006 peak / $0.003 off-peak. Peak hours are weekdays 01:00–04:00 and 06:00–10:00 UTC. Open weights (MIT). The legacy deepseek-v4-flash and deepseek-v4-flash-vision-exp ids temporarily route here. DeepSeek V4 Pro has tiered pricing: Official peak rates $1.32/$3.96 per MTok; off-peak $0.66/$1.98 (cache-miss). Cache hit $0.044 peak / $0.022 off-peak. Peak hours are weekdays 01:00–04:00 and 06:00–10:00 UTC. Open weights (MIT). 1.6T/49B active MoE.
Which has the larger context window, DeepSeek V4.1 Flash or DeepSeek V4 Pro?
Both accept about 1M tokens of context, so document length will not decide between them.
Do DeepSeek V4.1 Flash and DeepSeek V4 Pro support the same reasoning levels?
Yes — both accept the same effort settings: "low", "high", "max". Higher effort costs more and takes longer, so start low and raise it only where output quality actually improves.
Should I use DeepSeek V4.1 Flash or DeepSeek V4 Pro?
DeepSeek V4.1 Flash is the balanced tier and DeepSeek V4 Pro the frontier tier. The useful question is whether your hardest task actually fails on the cheaper one — most production volume such as classification, extraction and summarisation does not.

Next step

Choosing between them

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

  • Input price: DeepSeek V4.1 Flash costs $0.30 per 1M tokens versus $1.32 for DeepSeek V4 Pro — a 4.4x difference at the headline tier.
  • Measured capability: DeepSeek V4.1 Flash leads GPQA Diamond 90.9 to 90.1 (measured 2026-09-10).
  • Positioning: DeepSeek V4.1 Flash sits in the balanced tier, DeepSeek V4 Pro in the frontier tier — most production volume (classification, extraction, summarisation) does not need the pricier tier.
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