TokSuite–Comma is part of TokSuite, a suite of language models designed to study the impact of tokenizer choice on language model behavior under controlled conditions.
This model uses the Comma tokenizer and is otherwise identical to the other TokSuite models in architecture, training data, training budget, and initialization. The TokSuite setup ensures that any observed behavioral characteristics reflect properties of the tokenizer rather than differences in model size, data, or optimization.
Tokenizer
Tokenizer: Comma
Tokenization method: BPE
Vocabulary size: 64,000
Out-of-vocabulary handling: Byte-fallback
Language coverage: Multilingual
Pretokenization source: GPT-4
Processing details:
Numbers: Group by 3
Contractions: GPT-4
Unicode normalization: None
Whitespace / boundary markers: Learned
Zerowidth chars: Token
Why Comma?
Comma was included in TokSuite to represent a multilingual BPE tokenizer with modern GPT-4–style pretokenization. As described in the tokenizer selection rationale of the TokSuite paper, Comma exemplifies a design point where subword segmentation is combined with contemporary preprocessing choices for multilingual text.
Including Comma enables TokSuite to study tokenizer behavior in settings where:
BPE segmentation is used with byte fallback,
preprocessing follows GPT-4–style conventions,
and multilingual text is handled by a single shared tokenizer.
This makes Comma a representative example of recent multilingual BPE tokenizer design.
All models in TokSuite are trained using a fixed token budget, following common practice in large-scale language model training.
Training Procedure
Training steps: 100,000
Sequence length: 4096
Batch size: 256 sequences
Optimizer: AdamW
Peak learning rate: 1e-3
Learning rate schedule: Cosine decay with 2,000 warm-up steps
Weight decay: 0.1
Evaluation
Canonical Benchmarks
The model was evaluated on standard base language model benchmarks:
HellaSwag
ARC
PIQA
XNLI
TokSuite Logo
These evaluations verify that the model exhibits reasonable base language modeling behavior at its scale and training budget.
TokSuite Robustness Benchmark
TokSuite–Comma is evaluated on the TokSuite robustness benchmark, which measures sensitivity to real-world text perturbations, including:
orthographic and spelling variations,
diacritics presence and absence,
keyboard and input-method noise,
Unicode formatting and homoglyphs,
OCR and spacing artifacts,
LaTeX and STEM-style formatting.
Tokenization Robustness under Multilingual Text Perturbations
Values represent relative performance drop, computed as (Acc_clean − Acc_perturbed) / Acc_clean, where lower values indicate greater robustness.
PPerturbation types include:
Input: non-native keyboard input and romanization
Diacr.: optional diacritics
Orth.& Gram.: orthographic and grammatical errors
Morph: morphological variations including derivations, inflections, and contractions
Noise: homoglyph substitutions, OCR artifacts, typos, and spacing errors
LaTeX: LaTeX-style mathematical formatting
STEM: scientific diagrams and notational conventions
Unic.: Unicode styling characters
NEN denotes non-English inputs and EN denotes English inputs. The Avg column reports the average relative performance drop across all perturbation categories.
Model
Input (NEN)
Diacr. (NEN)
Orth. & Gram. (EN)
Orth. & Gram. (NEN)
Morph (EN)
Morph (NEN)
Noise (EN)
Noise (NEN)
LaTeX (EN)
STEM (EN)
Unic. (EN)
Avg ↓
TokenMonster
0.23
0.33
0.08
0.01
0.23
-0.07
0.10
0.18
0.21
0.10
0.51
0.17
XGLM
0.34
0.49
0.10
0.11
0.25
0.07
0.12
0.22
0.29
0.29
0.11
0.22
BLOOM
0.30
0.34
0.13
0.07
0.18
0.11
0.18
0.18
0.24
0.11
0.57
0.22
ByT5
0.30
0.44
0.04
0.06
0.27
0.04
0.14
0.18
0.17
0.29
0.53
0.22
Comma
0.28
0.43
0.05
0.07
0.18
0.00
0.11
0.20
0.23
0.29
0.61
0.22
mBERT
0.33
0.44
0.11
0.11
0.23
0.06
0.18
0.22
0.14
0.22
0.61
0.24
GPT-4o
0.30
0.51
0.08
0.05
0.21
0.05
0.16
0.19
0.24
0.33
0.55
0.24
GPT-2
0.34
0.46
0.07
0.10
0.25
0.06
0.14
0.21
0.24
0.35
0.53
0.25
Phi-3
0.33
0.46
0.16
0.09
0.27
0.08
0.17
0.21
0.24
0.22
0.55
0.25
Gemma-2
0.32
0.42
0.14
0.15
0.24
0.03
0.16
0.25
0.22
0.36
0.57
0.26
Qwen-3
0.36
0.42
0.14
0.11
0.25
0.06
0.16
0.23
0.26
0.29
0.57
0.26
Llama-3.2
0.33
0.55
0.11
0.10
0.25
0.08
0.15
0.24
0.17
0.30
0.59
0.26
Aya
0.31
0.46
0.14
0.10
0.22
0.03
0.19
0.25
0.21
0.38
0.58
0.26
Tekken
0.33
0.47
0.18
0.03
0.31
0.10
0.14
0.21
0.27
0.43
0.54
0.27
Avg
0.31
0.44
0.11
0.08
0.24
0.04
0.15
0.21
0.22
0.28
0.53
0.24
Intended Use
This model is intended for:
research on tokenization and robustness,
multilingual NLP analysis,
controlled ablation studies,
benchmarking tokenizer behavior under noise.
It is not instruction-tuned, aligned, or optimized for deployment.
Limitations
Trained on a limited set of five languages.
Not optimized for instruction following or dialogue.
Fixed token budget constrains exposure to raw text depending on tokenization efficiency.
Intended strictly for research purposes.
Ethical Considerations
TokSuite models are released to support scientific investigation of tokenization effects.
They may reflect biases present in large-scale web data and should not be used in high-stakes or user-facing applications without additional safeguards.
Citation
If you use this model, please cite:
bibtex
1@article{toksuite2025,
2 title={TokSuite: Measuring the Impact of Tokenizer Choice on Language Model Behavior},
3 author={Altıntaş, Gul Sena and Ehghaghi, Malikeh and Lester, Brian and Liu, Fengyuan and Zhao, Wanru and Ciccone, Marco and Raffel, Colin},
4 year={2025},
5 arxiv={https://arxiv.org/abs/2512.20757},
6}