I compared Opus 4.6 vs Kimi K2.5.. (Results SHOCKED me)

Quick Overview

Opus 4.6 was the best overall CRO audit tool among the four tested LLMs (Opus 4.6, Kimi K2.5, Opus 4.5, and Sonnet 4.5), primarily due to its most accurate observations, superior scoring system, and more realistic impact estimates, despite Sonnet 4.5 providing the best 'before and after' copy/paste examples.

Key Points: Opus 4.6 was declared the overall winner for CRO auditing due to its superior accuracy, scoring, and impact estimates compared to the other three models. Sonnet 4.5 provided the best 'before and after' copy/paste examples for headline changes, offering specific, ready-to-use replacements. Opus 4.6 had the most accurate observations, correctly identifying major issues like social proof contradictions and pricing inconsistencies. The best scoring system came from Opus 4.6, which scored pages on a 0-100 scale, whereas others used different or less granular scales. Kimi K2.5 was noted for being solid but slightly slower, while Opus 4.5 was deemed comprehensive but less systematic than Opus 4.6 or Sonnet 4.5. The creator plans to stop daily videos to focus on quality, possibly producing content a couple of times a month, due to the time commitment of testing. The creator tested the models by asking them to perform a CRO audit on localrank.so using the same prompts for all four LLMs.

Context: The video features a creator comparing the performance of four large language models (LLMs)—Opus 4.6, Kimi K2.5, Opus 4.5, and Sonnet 4.5—on a complex task: conducting a comprehensive Conversion Rate Optimization (CRO) audit for the website localrank.so. The creator used a specific set of prompts and uploaded the same set of MD files to each model to ensure a fair comparison across metrics like observation accuracy, scoring, revenue impact estimation, and strategic thinking.

Detailed Analysis

The creator compared four leading LLMs—Opus 4.6, Kimi K2.5, Opus 4.5, and Sonnet 4.5—on their ability to conduct a comprehensive CRO audit for a specific website, localrank.so. The comparison was set up by feeding each LLM the same four documents (MD files) and asking them to perform the audit, including providing concrete examples. The results showed that Claude Sonnet 4.5 provided the best 'before and after' copywriting examples, such as suggesting a headline change from generic to outcome-focused. However, Opus 4.6 was declared the overall winner. Opus 4.6 excelled in providing the most accurate observations, catching significant issues like social proof contradictions and pricing inconsistencies that other models missed or generalized. Its scoring system (0-100 scale) was also deemed superior. Kimi K2.5 was noted for solid performance but was slower, while Opus 4.5 was comprehensive but less systematic than the top two. The creator also validated several claims against the live site, confirming issues like a broken template bug and the accuracy of social proof numbers mentioned by the models. Ultimately, Opus 4.6 was validated against the actual site as the best overall CRO audit tool.