Model comparison

DeepSeek V4.1 Flash vs GPT-6 Luna

DeepSeek V4.1 Flash and GPT-6 Luna score almost the same on the Noometry Index (52.8 vs 53.3), so choose on price, context window or the category you care about most.

Last verified . 35 shared benchmarks.

DeepSeek V4.1 Flash DeepSeek

52.8

Rank #38 Confirmed

GPT-6 Luna OpenAI

53.3

Rank #36 Confirmed

Summary

  • They share 35 benchmarks with published results for both. DeepSeek V4.1 Flash scores higher in 6 categories and GPT-6 Luna in 4 categories; 9 gaps are clear of the uncertainty.
  • The widest gap is in math, where GPT-6 Luna leads 76.1 to 66.7.
  • The biggest single-benchmark swing is Mystery Game Puzzles: 43% for DeepSeek V4.1 Flash and 7% for GPT-6 Luna.
  • GPT-6 Luna is cheaper at $0.10 / $0.50 per million input/output tokens, against $0.15 / $0.60 for DeepSeek V4.1 Flash.
  • GPT-6 Luna accepts more context: 1.05M tokens versus 1M.
  • DeepSeek V4.1 Flash has downloadable open weights; the other is API-only.

Side by side

DeepSeek V4.1 Flash and GPT-6 Luna specifications
DeepSeek V4.1 FlashGPT-6 Luna
ProviderDeepSeekOpenAI
Noometry Index52.853.3
Released2026-09-092026-09-22
WeightsOpenProprietary
Context window1M1.05M
Max output393K128K
Input $ / M tokens$0.15$0.10
Output $ / M tokens$0.60$0.50
Results tracked3742

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Category by category

Coding GPT-6 Luna leads

DeepSeek V4.1 Flash: 52.9 (#32), GPT-6 Luna: 55.5 (#25)

Coding benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
LMArena WebDev16191581
SciCode51.9%54.6%
LMArena Coding15061439
ALE-Bench1,0921,577
DeepSWE—66.6%
FrontierCode—42.4%

Agentic & Tool Use GPT-6 Luna leads

DeepSeek V4.1 Flash: 31.2 (#69), GPT-6 Luna: 33.3 (#54)

Agentic & Tool Use benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
APEX-Agents39.5%44.3%
GDP.pdf19.8%23%

Reasoning DeepSeek V4.1 Flash leads

DeepSeek V4.1 Flash: 50.2 (#36), GPT-6 Luna: 48.2 (#41)

Reasoning benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
NYT Connections (extended)89.6%68.7%
CritPt14.3%19.4%
LMArena Hard Prompts14831411
Mystery Game Puzzles43%7%
DTBench89.9%90.1%
LMCA47%44.5%
Epoch Capabilities Index154.9156.28
ARC-AGI-2—59.3%
ARC-AGI-1—86.7%
Chess Puzzles—31%
Surface Evolver Bench46.3%—

Math GPT-6 Luna leads

DeepSeek V4.1 Flash: 66.7 (#25), GPT-6 Luna: 76.1 (#15)

Math benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
FrontierMath (Tiers 1-3)67.4%78.9%
FrontierMath Tier 426.8%56.1%
OTIS Mock AIME 2024-202598.3%98.9%
ProofBench54%64%
LMArena Math14771416

Knowledge Too close to call

DeepSeek V4.1 Flash: 57.9 (#38), GPT-6 Luna: 57.0 (#41)

Knowledge benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
GPQA Diamond89.8%90.5%
LMArena Expert15061444
SimpleQA Verified—41.4%

Multimodal GPT-6 Luna leads

DeepSeek V4.1 Flash: 39.1 (#61), GPT-6 Luna: 42.4 (#30)

Multimodal benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
LMArena Vision12771217
Furniture Assembly34.2%44.2%
Blueprint-Bench 2—31.2%

Multilingual DeepSeek V4.1 Flash leads

DeepSeek V4.1 Flash: 55.0 (#35), GPT-6 Luna: 50.5 (#117)

Multilingual benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
LMArena Non-English14481386
LMArena Chinese14971433
LMArena French14521420
LMArena German14841369
LMArena Japanese14121369
LMArena Korean14521360
LMArena Russian14711394
LMArena Spanish14591393

Instruction Following DeepSeek V4.1 Flash leads

DeepSeek V4.1 Flash: 77.3 (#26), GPT-6 Luna: 74.3 (#99)

Instruction Following benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
LMArena Instruction Following14741409

Long Context DeepSeek V4.1 Flash leads

DeepSeek V4.1 Flash: 45.2 (#47), GPT-6 Luna: 43.0 (#111)

Long Context benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
LMArena Longer Query14751409

Writing & Preference DeepSeek V4.1 Flash leads

DeepSeek V4.1 Flash: 65.4 (#48), GPT-6 Luna: 58.3 (#119)

Writing & Preference benchmarks
BenchmarkDeepSeek V4.1 FlashGPT-6 Luna
LMArena Text14621391
LMArena Creative Writing14351363
LMArena Multi-Turn14571396
EQ-Bench Creative Writing1540—

Frequently asked questions

Is DeepSeek V4.1 Flash better than GPT-6 Luna?

DeepSeek V4.1 Flash and GPT-6 Luna score almost the same on the Noometry Index (52.8 vs 53.3), so choose on price, context window or the category you care about most.

Which is cheaper, DeepSeek V4.1 Flash or GPT-6 Luna?

GPT-6 Luna is cheaper. It lists at $0.10 per million input tokens and $0.50 per million output tokens; DeepSeek V4.1 Flash lists at $0.15 and $0.60.

Is DeepSeek V4.1 Flash or GPT-6 Luna better for coding?

GPT-6 Luna scores higher on coding benchmarks: 55.5 versus 52.9 in the Noometry coding category.

Which has the bigger context window?

GPT-6 Luna does, with 1.05M tokens against 1M.

How many benchmarks do DeepSeek V4.1 Flash and GPT-6 Luna share?

35 benchmarks have published results for both models. DeepSeek V4.1 Flash has 37 scored results on Noometry and GPT-6 Luna has 42.

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