Which is better, Claude Opus 4.5 or Claude Opus 4.8?

Across 56 shared benchmarks tracked on Vector Wire, Claude Opus 4.5 leads on 7 and Claude Opus 4.8 leads on 49 — Claude Opus 4.8 leads on more. Strengths differ by axis; the table below shows every head-to-head number with provenance.

SEEDRefresh Models —Deals —Regulatory —Sources —

Claude Opus 4.5 vs Claude Opus 4.8

AnthropicvsAnthropic56 shared benchmarks7–49 head-to-head

Benchmark	Claude Opus 4.5	Claude Opus 4.8
AA Agentic Index	59.6	49.4
AA Intelligence	41.9	57.3
AA-LCR	76	73
AA-Omniscience	14	28.8
aime_2026	95.1	100
arc_agi_1	82	92.5
ARC-AGI-2	37.6	72.1
arena_elo	1473	1482
arena_text_factuality	1458	1464
Artificial Analysis Coding Index	47.8	74.3
browsecomp	37	88.5
charxiv_rq	68.5	80.5
coding_arena_elo	1495	1539
critpt	4.6	20.9
cybergym	50.6	83.1
deepsearchqa_f1	76.1	93.1
finance_agent	55.2	53.9
Fortress	13.6	18.2
frontiermath_tier_4	4.2	31.3
gdpval	47.3	54.2
GPQA Diamond	87	93.6
HLE	30.8	57.9
HLE (with tools)	43.4	57.9
hmmt_feb_2026	85.3	96.7
hmmt_nov_2025	93.3	96.5
IFBench	58	62.2
imo_answer_bench	84	83.5
livebench	76	77.2
livebench_agentic_coding	39.7	50.5
livebench_coding	79.7	81.8
livebench_data_analysis	74.4	66
livebench_instruction_following	62.5	72
livebench_language	81.3	79.7
livebench_math	90.4	94.3
livebench_reasoning	80.1	89.2
longbench_v2	64.4	69.1
mathvision	77.1	86.7
MCP Atlas	69.8	83.6
MMMU-Pro	74	78.9
MMVU	77.3	79.2
nl2repo	43.2	69.7
OmniScience Accuracy	46.6	48.8
OmniScience Non-Hallucination	39	60.7
OSWorld-Verified	66.3	83.4
PaperBench	72.9	80.3
scicode	50	53.5
simplebench	62	64.8
simpleqa_verified	41.8	39.5
SWE-bench Multilingual	77.5	84.4
SWE-bench Pro	57.1	69.2
SWE-bench Verified	81.5	88.6
Terminal-Bench 2.0	59.3	74.6
Terminal-Bench Hard	47	58.3
tool_decathlon	43.5	59.9
toolathlon	43.5	59.9
τ²-Bench Telecom (AA run)	89.5	94.4

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.