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The fastest Persian (Farsi) pipelines for spaCy: tagger, morphologizer, lemmatizer, dependency parser and NER.

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Persian (Farsi) pipelines for spaCy

Trained spaCy pipelines for Persian, installable with pip. spaCy has never shipped an official one, and spacy.blank("fa") only gives you a tokenizer and stop words. These add POS tags, morphology, lemmas, dependency parses and named entities, trained on the UD Persian PerDT treebank.

pip install https://huggingface.co/Phazel/fa_core_news_sm/resolve/main/fa_core_news_sm-3.8.0-py3-none-any.whl
>>> import spacy
>>> nlp = spacy.load("fa_core_news_sm")

>>> doc = nlp("محمدرضا شجریان در مشهد به دنیا آمد.")
>>> [(t.text, t.pos_, t.lemma_, t.dep_) for t in doc][:2]
[('محمدرضا', 'PROPN', 'محمدرضا', 'nsubj'), ('شجریان', 'PROPN', 'شجریان', 'flat:name')]
>>> doc.ents
(محمدرضا شجریان, مشهد)

>>> doc = nlp("وزارت نفت روز شنبه قیمت بنزین را ۱۰ درصد افزایش داد.")
>>> [(e.text, e.label_) for e in doc.ents]
[('وزارت نفت', 'ORG'), ('روز شنبه', 'DAT'), ('۱۰ درصد', 'PCT')]

Which package

Ten packages in four tiers. Three run on CPU, one wants a GPU:

  • sm: no static vectors. Smallest and fastest.
  • md: adds floret vectors (fastText-style vectors that hash subwords, so no word is out of vocabulary), 50k rows trained on 400,000 Persian Wikipedia articles.
  • lg: floret vectors, 200k rows trained on the full Persian Wikipedia.
  • trf: fine-tuned ParsBERT (a Persian BERT). Most accurate, needs a GPU.
You need sm md / lg trf
Tags, lemmas, parse fa_dep_news_sm fa_dep_news_md, fa_dep_news_lg fa_core_news_trf
Entities only fa_ent_news_sm fa_ent_news_md, fa_ent_news_lg fa_core_news_trf
Both fa_core_news_sm fa_core_news_md, fa_core_news_lg fa_core_news_trf

Packages

Package Size
fa_dep_news_sm 7.9 MB
fa_core_news_sm 13.5 MB
fa_ent_news_sm 5.9 MB
fa_dep_news_md 62.6 MB
fa_core_news_md 68.5 MB
fa_ent_news_md 60.6 MB
fa_dep_news_lg 229.3 MB
fa_core_news_lg 235.2 MB
fa_ent_news_lg 227.3 MB
fa_core_news_trf 608.2 MB

Install

HF=https://huggingface.co/Phazel
# syntax + NER, 13.5 MB
pip install $HF/fa_core_news_sm/resolve/main/fa_core_news_sm-3.8.0-py3-none-any.whl
# syntax only, 7.9 MB
pip install $HF/fa_dep_news_sm/resolve/main/fa_dep_news_sm-3.8.0-py3-none-any.whl
# NER only, 5.9 MB
pip install $HF/fa_ent_news_sm/resolve/main/fa_ent_news_sm-3.8.0-py3-none-any.whl

For the vector tiers, swap sm for md or lg in both the repo name and the filename:

pip install $HF/fa_core_news_md/resolve/main/fa_core_news_md-3.8.0-py3-none-any.whl
pip install $HF/fa_core_news_lg/resolve/main/fa_core_news_lg-3.8.0-py3-none-any.whl

fa_core_news_trf is versioned 1.0.0, not 3.8.0, and needs spacy-transformers:

pip install spacy-transformers
pip install $HF/fa_core_news_trf/resolve/main/fa_core_news_trf-1.0.0-py3-none-any.whl

Accuracy

Syntax scores are on the held-out test split of PerDT (UD_Persian-PerDT), the Persian Dependency Treebank in Universal Dependencies form: 29,107 sentences with gold UPOS, features, lemmas and dependencies. Entity scores use a separate NER layer over the same sentences, see Named entity recognition. Scores come from spacy benchmark accuracy and also ship in each package's meta.json.

What the metrics measure (percentages, higher is better):

  • TOKEN_ACC / TOKEN_F: how well the tokenizer finds word boundaries.
  • TAG_ACC: fine-grained part-of-speech tags (XPOS, PerDT's own tagset).
  • POS_ACC: coarse part-of-speech tags (UPOS, the 17 universal tags such as NOUN, VERB).
  • MORPH_ACC: morphological features such as number, person and tense.
  • LEMMA_ACC: the dictionary form of each word (کتاب‌ها → کتاب).
  • SENTS_F: sentence boundaries.
  • DEP_UAS (unlabeled attachment score): share of words attached to the correct head word.
  • DEP_LAS (labeled attachment score): the same, but the relation label (nsubj, obj, …) must also be right. Always at or below UAS.
  • ENTS_P / ENTS_R / ENTS_F: entity precision (share of predicted entities that are right), recall (share of real entities that were found), and F, the balance of the two.

Tier comparison

The md tier's config differs from sm by exactly one line (include_static_vectors), so the columns below isolate what the vectors buy. Full breakdown in docs/MODELS.md §6.

Metric sm md lg trf Reference
TOKEN_ACC / TOKEN_F 99.96 / 99.11 99.96 / 99.11 99.96 / 99.11 99.96 / 99.11
TAG_ACC (XPOS) 95.96 96.25 96.55 97.62
POS_ACC (UPOS) 96.24 96.64 96.68 97.63
MORPH_ACC 96.29 96.64 96.70 97.82
LEMMA_ACC 97.91 97.96 98.08 97.31
SENTS_F 99.25 99.28 99.18 97.35
DEP_UAS 89.69 90.52 90.96 93.87 hazm-bert-dependency-parser: 92.46
DEP_LAS 85.15 86.34 86.60 90.79 hazm-bert-dependency-parser: 89.34
ENTS_P 77.67 76.56 81.51 84.06
ENTS_R 66.87 72.95 71.09 81.76
ENTS_F 71.87 74.71 75.94 82.89
Speed (940MX, batch 32) 10,235 words/s 9,058 words/s 9,215 words/s 1,106 words/s
Wheel size 13.5 MB 68.5 MB 235.2 MB 608.2 MB

Reference cells are hazm-bert-dependency-parser's own meta.json, trained on the same treebank (docs/MODELS.md §4).

trf leads on every metric except lemmatization and sentence segmentation. It is also the only tier to clear the hazm-bert-dependency-parser DEP_LAS reference of 89.34. It needs a GPU in production (187 words/s on the laptop CPU), and its HooshvareLab/bert-base-parsbert-uncased encoder states no licence, so the published wheel carries a redistribution warning in its meta.json and its terms are unknown (docs/MODELS.md §8).

Entity scores are fa_core_news_* on the PerDT NER test split; per-label breakdown and caveats are in Named entity recognition.

Against Hazm and English

Compared against Hazm (https://github.com/roshan-research/hazm), the most widely used Python toolkit for Persian, and en_core_web_sm (English reference).

Metric This project
fa_core_news_trf
Hazm
(Persian toolkit)
en_core_web_sm
(English reference)
POS accuracy 97.63% UPOS 98.8% own tagset¹ 97.29% PTB XPOS²
Lemma accuracy 97.31% 89.9%¹ not reported²
Dependency UAS / LAS 93.87% / 90.79% 92.46% / 89.34%¹ 91.77% / 89.92%²
NER F-score 82.89% not reported¹ 84.33%²

¹ Hazm's own README, https://github.com/roshan-research/hazm#evaluation: POSTagger 98.8% on Hazm's own tagset (augmented with ezafe markers), which is not UPOS; Lemmatizer 89.9%. It reports no NER score. Parser scores are from hazm-bert-dependency-parser's meta.json, as in the tier comparison; Hazm's README quotes UAS 92.30 / LAS 89.15 for its SpacyDependencyParser.

² en_core_web_sm 3.8.0 meta.json, https://github.com/explosion/spacy-models/blob/master/meta/en_core_web_sm-3.8.0.json: tag_acc 0.9729, dep_uas 0.9177, dep_las 0.8992, ents_f 0.8433. That pipeline reports no pos_acc and no lemma_acc, because OntoNotes has no UPOS or lemma layer.

The three columns were scored on different test data.

Speed

Median of repeated nlp.pipe passes over the 146-document PerDT test split (23,825 words), timing the pipe only, warmup discarded. Reproduce with python scripts/benchmark_throughput.py <model> --gpu-id <n>, which writes the raw records to metrics/throughput-*.json.

Tier CPU, i5-7200U GPU, GeForce 940MX CPU, Xeon @ 2.00GHz GPU, Tesla T4
sm 5,484 10,235
md 5,408 9,058
lg 4,715 9,215
trf 187 1,106 336 8,320

trf is 29x slower than sm on the same CPU. The Xeon and T4 columns come from one Colab VM, a 25x GPU speedup. The CPU tiers sit within 15% of each other, so the bottleneck is the parser and lemmatizer, not the tok2vec lookup. Laptop numbers vary by about 10% with thermal state. Running trf on the 940MX needs a cu126 torch build, see docs/MODELS.md §9.

Against other Persian toolkits

The same 146 documents as raw text, full pipeline, same laptop CPU. Reproduce with scripts/benchmark_toolkit.py.

Toolkit Components Words/s
fa_dep_news_sm tokenizer, tagger, morphologizer, lemmatizer, parser 13,073
fa_core_news_sm the same, plus NER 8,831
UDPipe 1.4, persian-seraji-ud-2.5 model³ tokenizer, tagger, lemmatizer, parser 1,929
DadmaTools 2.3.6¹ tokenizer, lemmatizer, POS tagger, parser, on XLM-RoBERTa 96
Stanza 1.14, perdt models¹ tokenizer, MWT, POS tagger, lemmatizer, parser 82
Hazm 0.12.1² normalizer, tokenizers, POS tagger, lemmatizer, MaltParser 25

fa_dep_news_sm is 7x faster than UDPipe, 136x faster than DadmaTools and 160x faster than Stanza. md and lg stay within 15% of sm, so they lead too. trf, at 187 words/s, is slower than UDPipe but still faster than DadmaTools, Stanza and Hazm.

¹ Timed on the first 16 documents (2,396 words); the other rows use all 146.

² Timed on 2026-08-11 in one 933-second pass. Every other row was measured on 2026-09-28 with one thread per process.

³ Speed only. The UDPipe 1 models (UD 2.5) predate PerDT, so this row uses Seraji (UD_Persian-Seraji), a smaller Persian UD treebank.

This table and the one above come from different days with different background load, which is why fa_core_news_sm reads 5,484 there and 8,831 here. Compare within a table, not across.

Named entity recognition

Seven labels: LOC (location), PER (person), ORG (organisation), DAT (date), MON (money), TIM (time), PCT (percent). They come from PerDT's own not-to-release/Dadegan with NER tag/ layer, transferred onto this pipeline's tokenization by difflib at a 99.86% alignment rate (scripts/transfer_perdt_ner.py). Spans that could not be aligned exactly were dropped rather than guessed. That layer is silver: PerDT's README states it was produced by the BERT-based Beheshti-NER tagger with manual corrections for recall, so the ENTS_F numbers below partly reflect agreement with that tagger, not with human annotation.

Both that realigned layer and a four-label LLM relabelling of the same sentences (annotation/, guideline v2.2) are published as Phazel/fa-perdt-ner, CC BY-SA 4.0, keyed by PerDT sent_id; spacy project run hub-dataset rebuilds it. The relabelling is measured against the silver layer in docs/MODELS.md §10 and ships no model yet.

ner runs standalone with its own embedded tok2vec (fa_ent_news_sm, fa_ent_news_md, fa_ent_news_lg), or bundled into fa_core_news_sm, fa_core_news_md and fa_core_news_lg alongside the syntax pipeline. In trf it is trained jointly against the shared transformer instead, so there is no standalone trf variant.

Label sm F md F lg F trf F Train examples
LOC 80.24 84.05 83.66 87.78 4,954
PER 65.29 68.18 72.63 81.88 4,847
ORG 68.77 70.25 71.01 78.50 2,643
DAT 74.45 76.19 70.83 82.52 1,323
MON 73.68 84.21 88.89 88.89 205
TIM 66.67 66.67 61.54 50.00 135
PCT 57.14 33.33 57.14 33.33 121

MON, TIM and PCT have single-digit support in the test split, so their deltas are one or two entities changing hands, not signal. PER, LOC and ORG carry the split. The md gain over sm (ENTS_F 71.87 to 74.71) is almost entirely recall (+6.08): static vectors already know rare proper nouns, which sm can only learn from the training data. trf adds another +6.95 F over lg, again mostly recall (71.09 to 81.76), and its largest per-label gains are PER (+9.25) and DAT (+11.69).

Caveats

  • Some lemmas contain a space. Multiword tokens were merged, so کتاب‌هایش is one token tagged N_IANM_PR_JOPER with lemma کتاب او. This affects about 1.5% of tokens.
  • doc.noun_chunks under-fires. spacy/lang/fa/syntax_iterators.py upstream matches ClearNLP labels that do not exist in Universal Dependencies. Bug analysis and proposed upstream patch in docs/upstream/fa-noun-chunks.md.

Citation

If you use these pipelines or the fa-perdt-ner dataset, please cite:

@software{fazeli_2026_persian_spacy,
  author = {Fazeli, Mohammad},
  title  = {Persian (Farsi) pipelines for spaCy},
  year   = {2026},
  url    = {https://github.com/Fazel94/spacy-persian},
  note   = {Models: https://huggingface.co/Phazel}
}

The syntax and NER training data come from the PerDT treebank (UD_Persian-PerDT); cite it too when you report results.

For maintainers

Build

The corpora download as checksummed assets; the md and lg tiers also need a floret wheel, described below. Python 3.12:

python -m venv .venv
.venv/bin/python -m pip install -U pip
.venv/bin/python -m pip install -r requirements.txt

.venv/bin/python -m spacy project assets      # download + checksum the corpora
.venv/bin/python -m spacy project run all     # -> fa_dep_news_sm + fa_core_news_sm
.venv/bin/python -m spacy project run ent     # -> fa_ent_news_sm, NER alone
Command What it does
inspect annotation coverage of the treebanks (scripts/inspect_treebanks.py)
convert-ud CoNLL-U to DocBin with --merge-subtokens, plus the tokenizer-agreement report
transfer-ner align PerDT's NER layer onto that tokenization by difflib (scripts/transfer_perdt_ner.py)
convert-ner transferred IOB2 to DocBin
debug-data, debug-data-ner spacy debug data on both corpora before spending CPU
train-dep tagger + morphologizer + trainable_lemmatizer + parser
train-ner the ner component, with its own embedded tok2vec
finalize-dep write fa_dep_news_sm metadata: sources, licence, notes (scripts/finalize_pipeline.py)
evaluate-dep spacy benchmark accuracy on the held-out UD test split
assemble-core source ner into the dep pipeline to produce fa_core_news_sm
evaluate-core score the assembled pipeline on both test splits
finalize-meta re-run finalize on both, folding test scores into meta.json["performance"]
package build wheels + sdists for both
smoke run both pipelines over Persian text and print every annotation layer
finalize-ent write fa_ent_news_sm metadata from the standalone NER run
evaluate-ent spacy benchmark accuracy for the NER-only package
package-ent build the fa_ent_news_sm wheel + sdist

The two training runs are single-threaded and independent, so they can run concurrently.

The vector and transformer tiers are separate workflows:

.venv/bin/python -m spacy project run md      # -> fa_dep_news_md, fa_core_news_md
.venv/bin/python -m spacy project run lg      # -> fa_dep_news_lg, fa_core_news_lg
.venv/bin/python -m spacy project run trf     # -> fa_core_news_trf, GPU only

The md and lg workflows stop at the dep and core packages. fa_ent_news_lg is built by finalize-ent-lg, evaluate-ent-lg and package-ent-lg, which no workflow calls; run them by name.

md and lg start by unpacking a floret vector wheel that spacy project assets does not download, because it is built by this project rather than fetched. Put it in the repo root under the exact filename project.yml expects (vars.floret_wheel, vars.floret_lg_wheel):

curl -L -o fa_floret-0.1.0-py3-none-any-400k-documents.whl \
  https://huggingface.co/Phazel/fa_floret_400k/resolve/main/fa_floret_400k-0.1.0-py3-none-any.whl
curl -L -o fa_floret-0.1.0-py3-none-any-full-wiki-200k-5epoch.whl \
  https://huggingface.co/Phazel/fa-floret-wiki-vectors/resolve/main/fa_floret_wiki_200k-0.1.0-py3-none-any.whl

trf additionally needs spacy-transformers and a real GPU (vars.gpu_trf is 0); the 940MX needs a cu126 torch build in a separate venv, see docs/MODELS.md §9.

sm, md and lg were trained on a 4-core i5-7200U, CPU only: sm took 1h27m for syntax plus 17 min for NER, md 1h54m plus 25 min (the two md runs overlapped, so wall clock overstates each), lg about 2h08m plus 13 min. trf took 1h58m on a rented Colab T4.

Vector packages

Standalone floret vector packages (vectors only, pipeline: []), usable as --paths.vectors for your own training or as a plain embedding table:

# 50k rows x 300d, first 400,000 Persian Wikipedia articles (the md tier's table)
pip install https://huggingface.co/Phazel/fa_floret_400k/resolve/main/fa_floret_400k-0.1.0-py3-none-any.whl
# 50k rows x 300d, full Persian Wikipedia dump
pip install https://huggingface.co/Phazel/fa_floret_full_wiki/resolve/main/fa_floret_full_wiki-0.1.0-py3-none-any.whl
# 200k rows x 300d, full Persian Wikipedia dump, 5 epochs (the lg tier's table)
pip install https://huggingface.co/Phazel/fa-floret-wiki-vectors/resolve/main/fa_floret_wiki_200k-0.1.0-py3-none-any.whl

Raw fa.floret and fa.vec exports of the lg tier's 200k-row table are in fa-floret-wiki-vectors.

Design decisions

  1. --merge-subtokens. spaCy has no multiword-token layer, and PerDT splits pronominal clitics (پدرم into پدر + م). Measured on dev, merging gives token F 0.9887 against 0.9823 for the split version, costing 34 composite XPOS tags on 1.5% of tokens. Without it, 1.5% of gold tokens are boundaries the shipped tokenizer can never produce. See scripts/tokenization_report.py.
  2. ner carries its own tok2vec. A Tok2VecListener only resolves inside the pipeline it was trained in, so a listener-based component cannot be sourced elsewhere. configs/fa_ner_sm.cfg embeds the tok2vec instead, as en_core_web_sm does.
  3. morphologizer + trainable_lemmatizer instead of attribute_ruler + rule lemmatizer. The English pipelines derive UPOS from PTB tags by rule because OntoNotes has no UPOS. UD gives gold UPOS, FEATS and lemmas, which yields real pos_acc, morph_acc and lemma_acc numbers instead of unmeasurable rule coverage.
  4. PerDT, not Seraji: 3.7x more tokens, and Seraji has no PROPN tag.

Why not Hazm's own models

Hazm publishes spaCy-format pipelines on the HF Hub, so it was the obvious starting point. Four problems:

  • Its trainable models are pycrfsuite CRFs (hazm/sequence_tagger.py). The repo contains no config.cfg and no spacy train; the Spacy* classes only download pretrained pipelines.
  • Those pipelines are three single-task models (transformer + tagger, transformer + parser, transformer + chunker), each version: 0.0.0 with an empty license field, pinned to spaCy 3.6. Using all three costs three ParsBERT forward passes and gives no shared Doc.
  • Its tokenizer is incompatible with UD tokenization: the normaliser fuses ZWNJ (zero-width non-joiner) affixes and join_verb_parts() glues multi-word verb chains into single tokens.
  • Most corpora it reads (Bijankhan, Peykare, Hamshahri, raw PerDT) sit behind peykaregan.ir or dadegan.ir under research-only terms.

It did confirm the corpus choice: Hazm's own spaCy parser was trained on modified_fa_perdt-ud-train.spacy, the same treebank used here.

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