NewKW5-230M: the third generation, Kiswahili firstRead
Regnant

Models · Third generation · Base · Current

KW5-230M The third-generation base.

The third-generation base: 230M parameters, pretrained from scratch on 7.90B tokens of Kiswahili.

A base model continues text; it does not follow instructions. It is the foundation of KW5-230M-instruct, and the starting point for anyone fine-tuning a small Kiswahili model on their own data.

The KW5-230M model card banner: the Regnant mark and the name on a deep green ground beside a hive of square and triangular cells.
230.4M
Parameters
embeddings tied
24
Layers
896 wide, GQA 14:2
7.90B
Tokens
34.3 per stored parameter
Apache 2.0
Licence

How it was trained.

Corpus
5.58B tokens: the audited v2 corpus, translated educational web, long-form PDFs, Swahili FineWiki, generated arithmetic and dialogue
Tokens seen
7,895,777,280 over 15,060 steps of 524,288, about 1.4 passes
Architecture
Pre-norm decoder: RMSNorm with QK-norm, SwiGLU, RoPE, grouped-query attention (14 query, 2 key-value heads), Canon layers, document-boundary masking, tied embeddings
Schedule
Warmup-stable-decay; context 1,024, then 2,048 for the decay over the last 15%
Optimiser
Muon for matrices, AdamW for the tied embedding and the norms
Hardware
Kaggle TPU v5e-8, five sessions
Validation loss
2.3656 at step 15,000

How it measured.

Bits per byte, 120 MasakhaNEWS test articles
0.891 (KW5-149M 0.926, Goldfish 125M 0.894, XGLM-564M 1.122)
MasakhaNEWS-sw topic accuracy, n = 476
74.2% [70.0, 77.9]
Belebele-sw, n = 900
33.0% [30.0, 36.1], chance 25%
AfriXNLI-sw, n = 600
36.5%, p = 0.055 against chance

News is in the pretraining mix and the test articles were not checked for overlap, so bits per byte and MasakhaNEWS are in-domain. Every model compared beats chance on Belebele; none clears it on AfriXNLI.

What it does well.

  • Fluent Kiswahili continuation
  • Arithmetic with its working in the pretraining layout: 56 of 57 bare sums, 56 of 60 with brackets
  • Clears Chinchilla's 20 tokens per parameter with room
  • Encodes line by line, so line-initial words keep their word-boundary piece

What it gets wrong.

  • Not an instruction model
  • States facts confidently and wrongly
  • Loops on open prompts without a repetition penalty
  • Primarily Tanzanian Kiswahili; part of the corpus is machine-translated
  • No safety tuning

The family.

Run it on your own hardware.

The model card has the exact prompt format and the inference code.