Claude Opus 4.8 vs DeepSeek V4 Pro (0813)

Independent runs have rewritten this matchup, mostly into ties. Claude Opus 4.8's one clean, confirmed win is raw reasoning without tools (HLE 48.7 vs 41.0, both Artificial Analysis runs). DeepSeek V4 Pro posts a bigger SWE-bench Verified number (96.4 vs 88.6, both vals.ai) — but that benchmark is saturated (grade D here), and by our own methodology rankings on it are unreliable regardless of gap size. LiveCodeBench (87.82 vs 87.53) and GPQA Diamond (92.42 apiece) no longer count as ties either: both are now graded saturated (grade D, same reason as SWE-bench Verified above; LiveCodeBench joined on 2026-09-29 after vals.ai stopped running it) — near-identical scores there say the test has run out of headroom, not that the two models are evenly matched. Terminal-Bench looks close too (78.9 vs 78.7) but the numbers come from different evaluation harnesses (tbench.ai's official board vs Artificial Analysis's own runs) — not a fair comparison even though both sides are independently run. vals.ai, which ran both on one Terminus 2 harness, disagrees with "close": 71.91 for Opus 4.8 against 54.68 for DeepSeek V4 Pro 0813, a 17.2-point gap past the 10.6 band, though neither figure is this site's tracked row. DeepSeek's own numbers for multi-tool chores and professional tasks sit close behind Opus's independently-run scores on those two (74.1 vs 76.2, 25.7 vs 27.0) — but on long-horizon coding DeepSeek's self-reported number is actually ahead (62.7 vs 59.0). Since only Opus's side of any of these three has been independently checked, call all three unverified rather than tied or real — DeepSeek hasn't confirmed it's keeping pace, or ahead, just claimed it. Two newly-tracked benchmarks don't change the picture: LiveBench is another tie (76.2 vs 77.4, both independently run on the same harness), and ARC-AGI-2 doesn't add a comparable line — the two models' best publicly reported scores come from different reasoning-effort tiers (Opus 4.8's High-tier 72.1 vs DeepSeek's Max-tier 61.3), so there's no matched-tier pair to call. The launch chart's drama mostly dissolves under independent measurement; what survives is a price gap: at list rates DeepSeek costs about a sixth of Opus per output token ($3.96 vs $25.00).