Claude Opus 5 vs Opus 5.5 Effort Levels Benchmark

The resultMove from Opus 5 to Opus 5.5 at any effort level from low to xhigh and your Claude Code bill drops by roughly 40-50%. Instruction following doesn’t get worse. On my suite it got a little better.Then turn the dial to max and everything flips. Opus 5.5 at max wrote 70,320 output tokens. Opus 5 wrote 10,267. Opus 5.5 took 10 minutes 54 seconds where Opus 5 took 3 minutes 6 seconds, and it cost $2.51 against $1.13.Same ten prompts. Same effort setting. Two very different effort dials.TL;DROpus 5.5 is cheaper at low, medium, high and xhigh. Its cost ratios run 0.52-0.61x, all far outside the 1.04x run-to-run noise floor.Most of that saving is the price list, not the model. Opus 5.5’s cache reads cost 60% less than Opus 5’s, and cache traffic is 74-87% of the bill below max. Price Opus 5.5’s tokens at Opus 5’s rates and at high it comes to 0.98x Opus 5. Same cost footprint.At max, Opus 5.5 is a different product. Its output jumps to 16x its own low setting. Opus 5 only doubles…