ToolBlur Research · Corpus v1.0.0

Arabic Text Normalization Methodology

An open reference that states exactly what each rule changes—and what must not be mistaken for linguistic correction.

Scope and purpose

The rules create a working copy for search, matching and deduplication. They do not correct grammar or spelling, choose contextually correct words or replace the source text. Every transformation is deterministic: identical input and settings produce identical browser output.

Two normalization levels

Conservative — default

Removes optional marks and tatweel, folds Alef forms, converts digits and cleans spacing. Suitable for general matching when the original is retained.

Aggressive — opt in

Also folds Alef Maqsura and Hamza carriers. It increases recall while hiding orthographic distinctions, so it is not suitable for publication copies.

Reproducible examples

InputExpectedRule
اللُّغَةُ العَرَبِيَّةُاللغة العربيةRemove diacritics
العــربيةالعربيةRemove tatweel
إلى أحمد وآمالالي احمد وامالNormalize Alef
فتىفتيOptional: Alef Maqsura → Ya
عام ٢٠٢٦عام 2026Arabic-Indic digits → ASCII

Important limitations

  • Never replace authoritative Quranic, educational or quoted text with a stripped copy.
  • Aggressive folding can merge distinct words into one comparison form.
  • Version 1.0 does not automatically fold Persian or Urdu letter variants.
  • Word counts rely on whitespace and do not perform morphological analysis.
  • Test the rules on a representative sample before processing a full corpus.

License and citation

The test corpus is available under CC BY 4.0. When reusing it, cite: ToolBlur Arabic Text Normalization Test Corpus, version 1.0.0, with a link to this page.