Llmspeed lets you feel local AI model speeds before buying hardware

Llmspeed is a free, open-source web tool that plays dummy text at the speed a chosen model would run on a chosen device, so you can see what a given speed actually feels like before you buy a GPU or a Mac. Its numbers come from community benchmarks such as r/LocalLLaMA and localscore.ai, with gaps filled by estimates from similar setups or from hardware specs. It assumes a short prompt on a single device. On Hacker News (243 points, 77 comments), people like the idea: one says it helps decide whether spending $10,000 or more on hardware is worth it without downloading every model to test. But many owners report the numbers are off in both directions, for example an M2 Ultra running about twice as fast as the site shows for an M3 Ultra, and a 4090 owner getting far more than the site's estimate. One commenter who runs models at work says real agent workloads with long prompts run at a half to a third of benchmark speed. Several suggest renting a similar GPU for a few minutes instead. Rough consensus: good for a feel, not for a purchase decision. Sorted take: use it to rule hardware out, not in. Before buying a local AI box, rent similar hardware for an hour and run your own prompts at your real length.