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Bayanat Labs Arabic Token-Tax Index

LLM APIs bill and limit by tokens, and the same content usually takes more tokens in Arabic than in English. This index measures how many more, tokeniser by tokeniser, on parallel Arabic–English text from the United Nations: the Arabic/English token ratio with a bootstrap confidence interval, tokens per thousand words, characters per token and a diacritics round trip, and the cost of a page at the vendors' list prices. Short everyday sentences from Tatoeba in Standard, Egyptian and Algerian Arabic are measured too. It comes as a dataset with per-segment token counts, a leaderboard, and a harness that counts the tokens of any text and re-runs the measurement from the public sources.

By Bayanat Labs· Updated · CC BY 4.0· اقرأ بالعربية
LicenceCC BY 4.0 (index data and documentation); Apache-2.0 (harness code and leaderboard); UN sentence pairs under the United Nations Parallel Corpus disclaimer
Versionv0.1.0 · Index data, harness and leaderboard v0.1.0, measured on 16 October 2026 (UTC); the harness is tagged on GitHub and not on PyPI yet.
Published
Updated
Who it is forTeams that budget for, compare or choose LLMs for Arabic products and need the token overhead of Arabic against English, per tokeniser, with its uncertainty.
LevelBeginner

Arabic tokenizer Arabic token count LLM tokenizer comparison Arabic LLM cost token tax

Key numbers

12tokenisers measured
1.42median Arabic/English token ratio on the UN test set
0.93lowest ratio (ALLaM)
3.35highest ratio (Falcon3)
3990Arabic–English sentence pairs in the UN test set
5text slices: two UN sets and three Tatoeba sets
7model list prices
3vendors behind those prices
7tokenisers not measured in this version, each listed with its reason in the dataset

Counted by script from the released files. Each key number is read from a file in the Hugging Face dataset (meta/summary.json, meta/tokenisers.json, meta/slices.csv and meta/costs.csv) and pinned to its SHA-256; MANIFEST.json lists every file with its SHA-256.

Downloads and identifiers

Get started

Load the results with the datasets library, or install the harness from GitHub at the v0.1.0 tag to count the tokens of your own text; pip install arabic-token-tax-index will work once it is published on PyPI.

# Python
from datasets import load_dataset
results = load_dataset("Bayanat-Labs/arabic-token-tax-index", "results", split="train")

# Harness
pip install "git+https://github.com/Bayanat-Labs/arabic-token-tax-index@v0.1.0"
arabic-token-tax count "تقرير الأمين العام عن أعمال المنظمة"

What is released

PartLicenceIn this release
Index results, tokeniser metadata, costs, prices and diacritics probeCC BY 4.0Yes
Cleaned UN sentence pairs with per-segment token countsUnited Nations Parallel Corpus disclaimer, reproduced in full in the dataset NOTICE; credit the United Nations as the sourceYes
Harness: Python package and command lineApache-2.0Yes
Leaderboard on Hugging Face SpacesApache-2.0Yes

Attribution: Arabic Token-Tax Index by Bayanat Labs, CC BY 4.0. UN text: source, the United Nations. https://huggingface.co/datasets/Bayanat-Labs/arabic-token-tax-index

Intended uses

  • Estimate how many more tokens, and how much more money, Arabic content takes than the same content in English with a given tokeniser.
  • Compare tokenisers on the same parallel text, with a confidence interval for every ratio.
  • Count the tokens of your own Arabic text with every tokeniser in the index, or re-run the measurement from the public sources.

Out of scope

  • Judging model quality: fewer tokens means lower cost and more text per context window, not a better model.
  • Exact invoices: costs use the list prices shown on each vendor's page on the retrieval date (one of them is marked there as a promotional price), without batch, cache or other discounts.

Rights at a glance

Training, display, redistribution and synthetic-voice use are separate permissions.

UseStatusNote
TrainingAllowedIndex data under CC BY 4.0 with attribution; the UN sentence pairs under the United Nations Parallel Corpus disclaimer, crediting the United Nations.
DisplayAllowedCC BY 4.0, with attribution; credit the United Nations for UN text.
RedistributionAllowedIndex data under CC BY 4.0; harness code under Apache-2.0; UN text with the corpus disclaimer kept in full. The Tatoeba configuration holds sentence ids, counts and hashes.
Synthetic voiceNot applicableText only; no audio.

Limitations

  • Tokenisers whose files are not public, or sit behind an access request, are not measured in this version; the dataset lists each one with the reason.
  • An API service may count tokens differently from the published tokenizer file, for example by adding special tokens or using another revision.
  • Prices change; every price row records when and where it was read.
  • The UN text is formal Modern Standard Arabic and the Tatoeba slices are short everyday sentences, so compare ratios within a slice.
  • Install the harness from GitHub for now; it is not on PyPI yet.

Sources and licences

SourceLicenceRedistributed here
United Nations Parallel Corpus v1.0, 2015 test and development setsUnited Nations Parallel Corpus disclaimer (credit the United Nations)Yes
Tatoeba (Standard, Egyptian and Algerian Arabic with English)CC BY 2.0 FR (Tatoeba contributors)No
Tokenizer files published by the model developers, at pinned revisionsEach file under its own licence (listed in the harness configuration)No

Token counts, ratios, intervals, costs and the diacritics probe are by Bayanat Labs. The cleaned UN sentence pairs are distributed with the full United Nations Parallel Corpus disclaimer (NOTICE in the dataset). Tatoeba sentences are identified by id and hash. Tokenizer files are fetched from their publishers at run time and are not part of the release. Prices are facts read from the vendors' official price pages at the time stated in each row. Source details

How to cite

Cite as:

Bayanat Labs (2026). Arabic Token-Tax Index, version 0.1.0 (run 2026-10-16). Bayanat Labs. https://huggingface.co/datasets/Bayanat-Labs/arabic-token-tax-index

No DOI. Cite the URL in the citation above and the date you read it.

@misc{bayanatlabs2026arabictokentaxindex,
  author       = {{Bayanat Labs}},
  title        = {Arabic Token-Tax Index, version 0.1.0 (run 2026-10-16)},
  year         = {2026},
  month        = oct,
  howpublished = {\url{https://huggingface.co/datasets/Bayanat-Labs/arabic-token-tax-index}}
}

How we handle citations

Changelog

DateVersionChange
v0.1.0Index data and per-segment token counts on Hugging Face, the leaderboard on Hugging Face Spaces, and the harness, configuration and method on GitHub.

Corrections and removal requests

If something in this release should not be there, or is wrong, email hello@bayanatlabs.com. We handle removal requests within 30 days, and platform requests within 24 hours. How removal requests work

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