Which is better, Claude Opus 4.5 or DeepSeek-V4-Flash?

Across 45 shared benchmarks tracked on Vector Wire, Claude Opus 4.5 leads on 19 and DeepSeek-V4-Flash leads on 26 — DeepSeek-V4-Flash leads on more. Strengths differ by axis; the table below shows every head-to-head number with provenance.

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Claude Opus 4.5 vs DeepSeek-V4-Flash

AnthropicvsDeepSeek45 shared benchmarks19–26 head-to-head

Benchmark	Claude Opus 4.5	DeepSeek-V4-Flash
AA Agentic Index	59.6	61.3
AA Intelligence	41.9	51.8
AA-LCR	76	74.3
AA-Omniscience	14	-14.3
aime_2026	95.1	95.8
arc_agi_1	82	84
ARC-AGI-2	37.6	46
arena_elo	1473	1439
arena_text_factuality	1458	1434
Artificial Analysis Coding Index	47.8	69.1
browsecomp	37	73.2
BrowseComp (context management)	59.2	73.2
coding_arena_elo	1495	1431
critpt	4.6	16.6
cybergym	50.6	76.7
gdpval	47.3	52.9
GPQA Diamond	87	90.8
HLE	30.8	38.6
HLE (with tools)	43.4	45.1
hmmt_feb_2026	85.3	94.8
IFBench	58	79.2
imo_answer_bench	84	88.4
livebench_agentic_coding	39.7	46.8
livebench_coding	79.7	75
livebench_data_analysis	74.4	79.3
livebench_instruction_following	62.5	65.5
livebench_language	81.3	79.2
livebench_math	90.4	86.8
livebench_reasoning	80.1	86.6
LiveCodeBench	87	91.6
MCP Atlas	69.8	69
MMLU-Pro	90	86.4
nl2repo	43.2	54.2
OmniScience Accuracy	46.6	40.4
OmniScience Non-Hallucination	39	15.6
scicode	50	49.9
simplebench	62	46.3
simpleqa_verified	41.8	45
SWE-bench Multilingual	77.5	73.3
SWE-bench Pro	57.1	52.6
SWE-bench Verified	81.5	79
Terminal-Bench 2.0	59.3	56.9
Terminal-Bench Hard	47	38.6
toolathlon	43.5	70.3
τ²-Bench Telecom (AA run)	89.5	95.6

Best tracked score per model per benchmark (default configuration; source-attributed). ↓ marks lower-is-better metrics. Open either model for its full surface, provenance and pricing.