Model comparison

DeepSeek V4 Flash vs o3

DeepSeek V4 Flash is the stronger model overall, scoring 53.6 to 47.5 on the Noometry Index.

Last verified . 34 shared benchmarks.

DeepSeek V4 Flash DeepSeek

53.6

Rank #35 Confirmed

o3 OpenAI

47.5

Rank #61 Confirmed

Summary

  • They share 34 benchmarks with published results for both. DeepSeek V4 Flash scores higher in 7 categories and o3 in 1 category; 6 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where DeepSeek V4 Flash leads 53.7 to 32.0.
  • The biggest single-benchmark swing is ARC-AGI-2: 61.4% for DeepSeek V4 Flash and 6.5% for o3.
  • DeepSeek V4 Flash is cheaper at $0.15 / $0.60 per million input/output tokens, against $2 / $8 for o3.
  • DeepSeek V4 Flash accepts more context: 1M tokens versus 200K.
  • DeepSeek V4 Flash has downloadable open weights; the other is API-only.

Side by side

DeepSeek V4 Flash and o3 specifications
DeepSeek V4 Flasho3
ProviderDeepSeekOpenAI
Noometry Index53.647.5
Released2026-04-242025-04-16
WeightsOpenProprietary
Context window1M200K
Max output393K100K
Input $ / M tokens$0.15$2
Output $ / M tokens$0.60$8
Results tracked4163

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Category by category

Coding DeepSeek V4 Flash leads

DeepSeek V4 Flash: 47.9 (#59), o3: 46.8 (#64)

Coding benchmarks
BenchmarkDeepSeek V4 Flasho3
WeirdML63%52.4%
LMArena Coding14571408
ALE-Bench1,306933.55
SWE-bench Verified—62.3%
FrontierCode18.8%—
SWE-bench Verified (bash only)—58.4%
Aider Polyglot—81.3%
LMArena WebDev1582—
SciCode49.9%—
GSO—8.8%
CadEval—74%

Agentic & Tool Use Not comparable

DeepSeek V4 Flash: —, o3: 34.5 (#44)

Agentic & Tool Use benchmarks
BenchmarkDeepSeek V4 Flasho3
Berkeley Function Calling Leaderboard—63%
GDPval—30.8%
DeepResearch Bench—45.2%
OSWorld—23%
LMArena Search—1144
METR Time Horizons—65.4%

Reasoning DeepSeek V4 Flash leads

DeepSeek V4 Flash: 53.7 (#30), o3: 32.0 (#78)

Reasoning benchmarks
BenchmarkDeepSeek V4 Flasho3
ARC-AGI-261.4%6.5%
SimpleBench61.1%53.1%
Kagi LLM Benchmark52.2%67.6%
ARC-AGI-189%60.8%
CritPt16.6%1.4%
Chess Puzzles33%38%
LMArena Hard Prompts14441402
Mystery Game Puzzles34%29%
DTBench90.9%84.8%
LMCA41.7%39.7%
Epoch Capabilities Index154.49146.86
NYT Connections (extended)89.6%—
EnigmaEval—13.1%
ForecastBench—62.5

Math DeepSeek V4 Flash leads

DeepSeek V4 Flash: 60.3 (#37), o3: 50.2 (#58)

Knowledge Too close to call

DeepSeek V4 Flash: 55.4 (#48), o3: 54.6 (#52)

Knowledge benchmarks
BenchmarkDeepSeek V4 Flasho3
GPQA Diamond91%81.8%
SimpleQA Verified33.6%49.4%
LMArena Expert14411402
Humanity's Last Exam—20.3%
MMLU-Pro—85.9%
Confabulations—14.4%
GPQA (HELM)—75.3%

Multimodal Not comparable

DeepSeek V4 Flash: —, o3: 41.4 (#36)

Multimodal benchmarks
BenchmarkDeepSeek V4 Flasho3
LMArena Vision—1214
GeoBench—74%
VPCT—52%

Multilingual DeepSeek V4 Flash leads

DeepSeek V4 Flash: 53.0 (#72), o3: 51.7 (#105)

Multilingual benchmarks
BenchmarkDeepSeek V4 Flasho3
LMArena Non-English14201401
LMArena Chinese14681437
LMArena French14391430
LMArena German14181420
LMArena Japanese14061403
LMArena Korean13841370
LMArena Russian14281406
LMArena Spanish14361395

Instruction Following DeepSeek V4 Flash leads

DeepSeek V4 Flash: 74.9 (#81), o3: 72.8 (#127)

Instruction Following benchmarks
BenchmarkDeepSeek V4 Flasho3
LMArena Instruction Following14211368
IFEval—86.9%

Long Context o3 leads

DeepSeek V4 Flash: 43.8 (#85), o3: 53.3 (#6)

Long Context benchmarks
BenchmarkDeepSeek V4 Flasho3
LMArena Longer Query14341372
Fiction.LiveBench—88.9%
CL-bench—17.8%

Writing & Preference Too close to call

DeepSeek V4 Flash: 63.8 (#61), o3: 63.5 (#64)

Writing & Preference benchmarks
BenchmarkDeepSeek V4 Flasho3
LMArena Text14321410
LMArena Creative Writing14031359
EQ-Bench Creative Writing15591676
LMArena Multi-Turn14491405
Short-Story Creative Writing—83.9%
WildBench—86.1%

Frequently asked questions

Is DeepSeek V4 Flash better than o3?

DeepSeek V4 Flash is the stronger model overall, scoring 53.6 to 47.5 on the Noometry Index.

Which is cheaper, DeepSeek V4 Flash or o3?

DeepSeek V4 Flash is cheaper. It lists at $0.15 per million input tokens and $0.60 per million output tokens; o3 lists at $2 and $8.

Is DeepSeek V4 Flash or o3 better for coding?

DeepSeek V4 Flash scores higher on coding benchmarks: 47.9 versus 46.8 in the Noometry coding category.

Which has the bigger context window?

DeepSeek V4 Flash does, with 1M tokens against 200K.

How many benchmarks do DeepSeek V4 Flash and o3 share?

34 benchmarks have published results for both models. DeepSeek V4 Flash has 41 scored results on Noometry and o3 has 63.

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