Open SLM Leaderboard: leaderboard

The Open SLM Leaderboard (Axiomic Labs, Hugging Face Space) ranks open-weight language models under 400M parameters that their submitters pretrained from scratch, with zero-shot scores from LM-eval harness and Axiomic Labs' ArithMark-3 script that the leaderboard team checks before merging. Unlike the Hugging Face Open LLM Leaderboard, which evaluated every submitted model on its own cluster, it lists zero-shot results the submitters ran and admits only small from-scratch checkpoints (no merges). The page does not state the harness version, the accuracy variant (acc or acc_norm) or the evaluated splits. Rows are bound to their Hugging Face model card; a row without one (Mystery-5M-Preview) is withheld, and a row missing a score is absent from that board only. Intelligence Index, the page's headline: each score is rescaled so chance is 0 and perfect is 100 (HellaSwag, ARC and ArithMark-3 chance 25, PIQA chance 50), then Index = (HellaSwag + mean of ARC-Easy and ARC-Challenge + PIQA + 0.65 x ArithMark-3) / 3.65; models below chance score below zero (floor -51.6). Admitted only for rows with all five inputs; ArithMark-2, the superseded arithmetic set kept in the expanded columns, is not part of the Index and is not admitted.

Metric: Intelligence Index: chance-normalized HellaSwag, combined ARC, PIQA and 0.65 x ArithMark-3, divided by 3.65 (0 = chance, 100 = perfect; below chance is negative). Source: huggingface.co. Saturation forecast: Rough model projection: around 2026. 255 models tracked.

Top models

#ModelScoreOverall rank
1SmolLM2-360M (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=HuggingFaceTB/SmolLM2-360M)41.86
2MobileLLM-R1-360M-base (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=facebook/MobileLLM-R1-360M-base)38.65
3KLM-1.6 (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=MinimaLabs/KLM-1.6)33.95
4GPT-X3-150M (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=AxiomicLabs/GPT-X3-150M)33.05
5Inferno-Exp-1.7 (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=AlgoDriveAI/Inferno-Exp-1.7)32.02
6LFM-2.5-350M-Base (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=LiquidAI/LFM2.5-350M-Base)30.62
7Boris-2-Preview-2 (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=opencerebral/Boris-2-Preview-2)30.58
8KLM-1.5 (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=MinimaLabs/KLM-1.5)30.26
9BananaMind-2.5-Pro (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=BananaMind/BananaMind-2.5-Pro)28.98
10Rose-1.5-Pro (Benchmark Sweep Run: source=Open SLM Leaderboard; zero-shot; card=GODELEV/Rose-1.5-Pro)28.27

Interactive version: theaggregate.ai/benchmark?slug=open-slm-leaderboard · How It Works · Data refreshed daily, snapshot 2026-11-12.