gpt-5.6 vs llama-3.1-8b-instant

Capability for the money

Not the same tier: gpt-5.6 leads llama-3.1-8b-instant by 68.2 points on hard reasoning (GPQA Diamond), for 195.7× the price.

1. Following instructions

   extraction, classification, sticking to a format

   IFBench
   gpt-5.672.7%

   llama-3.1-8b-instant28.6%

   gpt-5.6 +44.1

2. Tool use

   multi-step agent work against real tools

   τ²-bench
   gpt-5.685.1%

   llama-3.1-8b-instant16.4%

   gpt-5.6 +68.7

3. Hard reasoning

   graduate-level science and multi-step analysis

   GPQA Diamond
   gpt-5.694.1%

   llama-3.1-8b-instant25.9%

   gpt-5.6 +68.2

Averaged over the benchmarks both models sat, llama-3.1-8b-instant returns 411.0 points of pass rate per dollar of blended price against 7.5 — the ratio that decides whether the dearer model earns its rate.

Each figure is a pass rate: the share of that test set the model answered correctly, measured by a third party rather than self-reported by the lab. Rows are different tests of different difficulty, so compare a model against the other model, not one row against the next. No published coding score for one of these models, so that lens is omitted. And a benchmark is not your workload — it narrows the shortlist, it does not pick for you.