Claude Opus 4.5 vs ZAYA1-8B

Pick Claude Opus 4.5 if you want the stronger benchmark profile. ZAYA1-8B only becomes the better choice if knowledge is the priority or you want the cheaper token bill.

Claude Opus 4.5 is clearly ahead on the provisional aggregate, 77 to 62. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Claude Opus 4.5's sharpest advantage is in instruction following, where it averages 79.4 against 74. The single biggest benchmark swing on the page is GPQA, 87% to 71%. ZAYA1-8B does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.

Claude Opus 4.5 is also the more expensive model on tokens at $5.00 input / $25.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for ZAYA1-8B. That is roughly Infinityx on output cost alone. ZAYA1-8B is the reasoning model in the pair, while Claude Opus 4.5 is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Claude Opus 4.5 gives you the larger context window at 200K, compared with 131K for ZAYA1-8B.