Claude Opus 4.6 vs DeepSeek-V4-Flash
Wins 5 of 7 areas
Coding · Agents · Reasoning · Facts · Math
Wins 2 of 7 areas
Long documents · Following instructions
Claude Opus 4.6 is the stronger all-rounder.DeepSeek-V4-Flash is cheaper and better at following instructions.
Scores updated · 52 tests both models report · How we compare
Where each one wins
Tests won in each of the seven areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- CodingWriting and fixing software71Claude Opus 4.67 of 9 tests · 1 tie
- MathCompetition and research-level math41Claude Opus 4.64 of 6 tests · 1 tie
- FactsGetting facts right instead of making them up30Claude Opus 4.63 of 3 tests
- ReasoningHard problems that need careful thinking42Claude Opus 4.64 of 6 tests
- AgentsCarrying out multi-step tasks on its own21Claude Opus 4.62 of 3 tests
- Following instructionsDoing exactly what it is asked02DeepSeek-V4-Flash2 of 2 tests
- Long documentsFinding answers in very long texts01DeepSeek-V4-Flash1 of 1 test
Long documents rests on a single test.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
DeepSeek-V4-Flash costs 94% less for the same work.
The biggest differences
The three tests each model wins by the widest margin. Scores are out of 100.
Where Claude Opus 4.6 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+28.9points ahead
- Common-sense trick questionsSimpleBench+21.3points ahead
- Short factual questions, answered correctlySimpleQA Verified+12.9points ahead
Where DeepSeek-V4-Flash pulls ahead
- Follows unfamiliar, precisely checkable instructionsIFBench+26.1points ahead
- Olympiad math problems with short answersIMOAnswerBench+13.1points ahead
- Multi-step tasks using many real software toolsMCP Atlas+6.3points ahead
Every test, side by side
All 52 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingClaude Opus 4.6
- LMArena · WebDevClaude Opus 4.6 by 116 rating points15461430+116 rating
- Terminal-Bench HardClaude Opus 4.6 by 10.646.235.6+10.6
- SWE-bench MultilingualClaude Opus 4.6 by 4.577.873.3+4.5
- LiveBench · CodingClaude Opus 4.6 by 3.278.275+3.2
- LiveBench · Agentic CodingClaude Opus 4.6 by 2.24946.8+2.2
- LiveCodeBench v6DeepSeek-V4-Flash by 1.888.890.6+1.8
- SWE-bench VerifiedClaude Opus 4.6 by 1.880.879+1.8
- SciCodeClaude Opus 4.6 by 1.651.950.3+1.6
- SWE-bench Protie53.452.6tie
AgentsClaude Opus 4.6
- BrowseCompClaude Opus 4.6 by 10.88473.2+10.8
- GDPValClaude Opus 4.6 by 955.946.9+9
- MCP AtlasDeepSeek-V4-Flash by 6.362.769+6.3
ReasoningClaude Opus 4.6
- SimpleBenchClaude Opus 4.6 by 21.367.646.3+21.3
- ARC-AGI-2Claude Opus 4.6 by 7.468.861.4+7.4
- CritPtDeepSeek-V4-Flash by 412.616.6+4
- LiveBench · ReasoningClaude Opus 4.6 by 2.188.786.6+2.1
- Humanity's Last ExamClaude Opus 4.6 by 1.339.938.6+1.3
- GPQA DiamondDeepSeek-V4-Flash by 1.289.690.8+1.2
FactsClaude Opus 4.6
- AA-Omniscience · Non-hallucinationClaude Opus 4.6 by 28.937.28.3+28.9
- SimpleQA VerifiedClaude Opus 4.6 by 12.94734.1+12.9
- AA-Omniscience · AccuracyClaude Opus 4.6 by 6.64740.4+6.6
MathClaude Opus 4.6
- IMOAnswerBenchDeepSeek-V4-Flash by 13.175.388.4+13.1
- FrontierMath Tiers 1-3 (v2)Claude Opus 4.6 by 8.56657.5+8.5
- LiveBench · MathematicsClaude Opus 4.6 by 2.589.386.8+2.5
- FrontierMath Tier 4Claude Opus 4.6 by 2.426.824.4+2.4
- HMMT Feb. 2026Claude Opus 4.6 by 1.496.294.8+1.4
- AIME 2026tie96.795.8tie
Following instructionsDeepSeek-V4-Flash
- IFBenchDeepSeek-V4-Flash by 26.153.179.2+26.1
- LiveBench · Instruction FollowingDeepSeek-V4-Flash by 2.263.365.5+2.2
Other results22 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- AA-OmniscienceClaude Opus 4.6 by 2813.7-14.3+28
- AA Agentic IndexClaude Opus 4.6 by 25.967.641.7+25.9
- GDPval-AA (Elo)Claude Opus 4.6 by 224 rating points16191395+224 rating
- Artificial Analysis Coding IndexDeepSeek-V4-Flash by 2148.169.1+21
- OpenAI-MRCR (1M)Claude Opus 4.6 by 14.292.978.7+14.2
- ToolathlonDeepSeek-V4-Flash by 13.556.870.3+13.5
- CorpusQA 1M (ACC)Claude Opus 4.6 by 11.271.760.5+11.2
- livebench_data_analysisDeepSeek-V4-Flash by 9.469.979.3+9.4
- Terminal-Bench 2.0Claude Opus 4.6 by 8.565.456.9+8.5
- HLE (with tools)Claude Opus 4.6 by 8.253.345.1+8.2
- JobBenchDeepSeek-V4-Flash by 4.736.641.3+4.7
- NL2RepoDeepSeek-V4-Flash by 4.449.854.2+4.4
- livebench_languageClaude Opus 4.6 by 4.183.379.2+4.1
- ARC-AGI-1Claude Opus 4.6 by 49389+4
- CyberGymDeepSeek-V4-Flash by 2.973.876.7+2.9
- MMLU-ProClaude Opus 4.6 by 2.989.186.2+2.9
- τ²-Bench Telecom (AA run)DeepSeek-V4-Flash by 2.992.195+2.9
- LiveCodeBenchDeepSeek-V4-Flash by 2.888.891.6+2.8
- Chinese SimpleQA (C-SimpleQA)DeepSeek-V4-Flash by 2.576.478.9+2.5
- AA IntelligenceDeepSeek-V4-Flash by 2.431.934.3+2.4
- Apex (Pass@1)Claude Opus 4.6 by 1.534.533+1.5
- Apex Shortlist (Pass@1)tie85.985.7tie
Questions people ask
Which is better, Claude Opus 4.6 or DeepSeek-V4-Flash?
Claude Opus 4.6 wins five of the seven areas where both have results: coding, agents, reasoning, facts and math. DeepSeek-V4-Flash wins long documents and following instructions, and costs 94% less.
Which is better for coding?
Claude Opus 4.6. It wins 7 of the 9 coding tests both models report; DeepSeek-V4-Flash wins 1, and 1 is a tie.
Which is cheaper?
Claude Opus 4.6 costs $5.00 per million input tokens and $25.00 per million output tokens; DeepSeek-V4-Flash costs $0.44 and $1.32. That makes DeepSeek-V4-Flash about 94% cheaper for the same work.
How do you compare the two?
We use the 52 benchmark tests both models have published scores on. The verdict counts the 30 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 22 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.