Compare / head-to-head

DeepSeek V4 FlashvsGPT-6 Luna

DeepSeek V4 Flash leads 9 of 17 shared benchmarks. GPT-6 Luna has the larger context window (1.1M tokens).

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
9 – 8
DeepSeek V4 Flash leads
Cheaper per token
—
list price, input + output
Larger context
GPT-6 Luna
1.1M tokens
Providers
2 providers
DeepSeek · OpenAI
DeepSeek V4 Flash
DeepSeek · released 2026-07-31
text
Context
1M
Max out
—
Input /1M
—
Output /1M
—
Cached /1M
—
Scores
28 · 7 core
GPT-6 Luna
OpenAI · released 2026-09-22
textvision
Context
1.1M
Max out
128K
Input /1M
$0.1 ↗
Output /1M
$0.5 ↗
Cached /1M
$0.01
Scores
22 · 8 core
Quality

Benchmark matrix

BenchmarkDeepSeek V4 FlashGPT-6 LunaΔEdge
Reported by both · 17
GPQA Diamond91% ↗epoch run90.5% ↗epoch run+0.5 ptDeepSeek V4 Flash
LMArena Elo1436 ↗1442.9 ↗-6.9GPT-6 Luna
Chess Puzzles (Epoch AI run)33% ↗epoch run31% ↗epoch run+2 ptDeepSeek V4 Flash
FrontierMath Tier 4 v2 (Epoch AI run)24.4% ↗epoch run56.1% ↗epoch run-31.7 ptGPT-6 Luna
FrontierMath Tiers 1-3 v2 (Epoch AI run)57.5% ↗epoch run78.9% ↗epoch run-21.4 ptGPT-6 Luna
LiveBench Agentic Coding (LiveBench)46.8% ↗51.2% ↗-4.4 ptGPT-6 Luna
LiveBench Coding (LiveBench)75% ↗79% ↗-4 ptGPT-6 Luna
LiveBench Data Analysis (LiveBench)79.3% ↗73.4% ↗+5.9 ptDeepSeek V4 Flash
LiveBench Instruction Following (LiveBench)65.5% ↗55.9% ↗+9.6 ptDeepSeek V4 Flash
LiveBench Language (LiveBench)79.2% ↗73.8% ↗+5.4 ptDeepSeek V4 Flash
LiveBench Mathematics (LiveBench)86.8% ↗89.1% ↗-2.3 ptGPT-6 Luna
LiveBench Reasoning (LiveBench)86.6% ↗81.8% ↗+4.8 ptDeepSeek V4 Flash
LMArena WebDev (LMArena)1581 ↗1578.7 ↗+2.3DeepSeek V4 Flash
Mystery Game Puzzles (Epoch AI run)34% ↗epoch run7% ↗epoch run+27 ptDeepSeek V4 Flash
OTIS Mock AIME 2024-2025 (Epoch AI run)94.4% ↗epoch run98.9% ↗epoch run-4.5 ptGPT-6 Luna
SimpleQA Verified33.6% ↗epoch run41.4% ↗epoch run-7.8 ptGPT-6 Luna
Terminal-Bench 4.0 (Vals AI)18.7% ↗13.6% ↗+5.1 ptDeepSeek V4 Flash
Only DeepSeek V4 Flash reports · 11
Agents' Last Exam25.2% ↗not reported——
AutomationBench Public25.1% ↗not reported——
Cybergym76.7% ↗not reported——
DeepSWE54.4% ↗not reported——
DeepSWE v1.1 (Datacurve)53.3% ↗not reported——
NL2Repo54.2% ↗not reported——
SimpleBench (SimpleBench)61.1% ↗not reported——
Terminal Bench 2.182.7% ↗not reported——
Toolathlon-Verified70.3% ↗not reported——
Toolathlon-Verified (HKUST)70.7% ↗not reported——
WeirdML (Håvard Tveit Ihle)63% ↗not reported——
Only GPT-6 Luna reports · 5
APEX-Agents (Mercor)not reported44.3% ↗——
DeepSWE v1.1not reported66.6% ↗——
Furniture Assembly (Epoch AI run)not reported44.2% ↗epoch run——
LMArena Agent (LMArena)not reported0.0135 ↗——
SAGE (Vals AI)not reported48.1% ↗——
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is DeepSeek V4 Flash minus GPT-6 Luna in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecDeepSeek V4 FlashGPT-6 LunaEdge
Context window1M tokens1.1M tokensGPT-6 Luna
Max output—128K tokens—
Input price / 1M—$0.1 ↗—
Output price / 1M—$0.5 ↗—
Cached input / 1M—$0.01 ↗—
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
—$0.6—
Modalitiestexttext · visionGPT-6 Luna
Released2026-07-312026-09-22—
Cited benchmark scores2822—
Reliability

Provider status

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