grok-4-1-fast vs grok-4-1-fast-reasoning

Capability for the money

Both are priced within 15% of each other, so capability decides it: grok-4-1-fast-reasoning leads by 42.3 points on coding (LiveCodeBench).

1. Following instructions

   extraction, classification, sticking to a format

   IFBench
   grok-4-1-fast36.5%

   grok-4-1-fast-reasoning52.7%

   grok-4-1-fast-reasoning +16.2

2. Coding

   writing and fixing code

   LiveCodeBench
   grok-4-1-fast39.9%

   grok-4-1-fast-reasoning82.2%

   grok-4-1-fast-reasoning +42.3

3. Tool use

   multi-step agent work against real tools

   τ²-bench
   grok-4-1-fast63.7%

   grok-4-1-fast-reasoning93.3%

   grok-4-1-fast-reasoning +29.6

4. Hard reasoning

   graduate-level science and multi-step analysis

   GPQA Diamond
   grok-4-1-fast63.7%

   grok-4-1-fast-reasoning85.3%

   grok-4-1-fast-reasoning +21.6

Averaged over the benchmarks both models sat, grok-4-1-fast-reasoning returns 285.0 points of pass rate per dollar of blended price against 185.3 — 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. And a benchmark is not your workload — it narrows the shortlist, it does not pick for you.