Among the first things a student of tajwīd learns are the rules of the silent nūn (nūn sākinah) and tanwīn. They are the key to precise recitation and appear on almost every page of the muṣḥaf. In this beginner-friendly guide we explain the four rulings — iẓhār, idghām, iqlāb, and ikhfāʾ — according to the reading of Ḥafṣ ʿan ʿĀṣim, with clear Quranic examples you can apply in your daily recitation.
What Are Nūn Sākinah and Tanwīn?
Nūn sākinah is a nūn with no vowel. It is fixed in both pronunciation and writing, whether you continue or stop, and occurs in nouns, verbs, and particles — as in al-anʿām, min, and ʿan. Tanwīn is an extra silent nūn attached to the end of a noun in pronunciation but not in writing; it is voiced when continuing and dropped when stopping, as in samīʿun, ʿalīman, qarībin. Because the two sound identical, scholars treat them under one chapter with four rulings, determined by the letter that follows.
These rules are not academic luxury: they preserve the beauty of recitation, regulate the nasal sound (ghunnah), and protect the reciter from subtle errors. That is why they are taught first in tajwīd circles, right after the articulation points of the letters.
The First Ruling: Iẓhār (Clear Pronunciation)
Iẓhār linguistically means making clear. Technically, it is pronouncing the nūn sākinah or tanwīn plainly from its articulation point, without a prolonged ghunnah. Its six letters all come from the throat: hamzah, hāʾ, ʿayn, ḥāʾ, ghayn, and khāʾ. Whenever one of them follows a nūn sākinah or tanwīn, the nūn is pronounced clearly and crisply.
- "wa-hum yanʾawna ʿanhu" [al-Anʿām: 26] — nūn sākinah followed by hamzah.
- "min khawf" [Quraysh: 4] — nūn sākinah followed by khāʾ.
- "anʿamta ʿalayhim" [al-Fātiḥah: 7] — nūn sākinah followed by ʿayn.
- "ʿadhābun alīm" [al-Baqarah: 10] — tanwīn followed by hamzah.
The Second Ruling: Idghām (Merging)
Idghām means merging the nūn sākinah or tanwīn into the following letter so the two become one doubled letter. Its six letters are gathered in the word "yarmalūn", in two categories: merging with ghunnah for the letters of "yanmū" (yāʾ, nūn, mīm, wāw), and merging without ghunnah for lām and rāʾ. Examples: "fa-man yaʿmal mithqāla dharratin khayran yarah" [al-Zalzalah: 7] with ghunnah; "ʿalā hudan min rabbihim" [al-Baqarah: 5] without ghunnah; and, for tanwīn before lām, "hudan lil-muttaqīn" [al-Baqarah: 2].
An Important Note: Absolute Iẓhār
Idghām requires the nūn to end one word and the merging letter to begin the next. If both occur inside a single word, clear pronunciation is obligatory — called absolute iẓhār. It occurs in only four Quranic words: dunyā, bunyān, ṣinwān, and qinwān, where the nūn stays clear to preserve the word's meaning.
The Third Ruling: Iqlāb (Conversion)
Iqlāb is converting the nūn sākinah or tanwīn into a hidden mīm before the letter bāʾ, keeping the ghunnah for two counts. It has one letter only: bāʾ. Examples include "anbiʾhum bi-asmāʾihim" [al-Baqarah: 33] and "samīʿun baṣīr". In vocalized copies of the muṣḥaf it is marked by a small mīm placed above the nūn or in place of the second tanwīn mark.
The Fourth Ruling: Ikhfāʾ (Concealment)
Ikhfāʾ is a state between iẓhār and idghām: the nūn is pronounced neither fully clear nor fully merged, without doubling, while the ghunnah remains for two counts and the tongue prepares for the next letter. Its letters are the remaining fifteen after the letters of the other three rulings, gathered by scholars in the first letters of a famous mnemonic verse.
Quranic examples include "man dhā alladhī yashfaʿu ʿindahu illā bi-idhnih" [al-Baqarah: 255], "alladhīna hum ʿan ṣalātihim sāhūn" [al-Māʿūn: 5], and the word "minkum" wherever it occurs. Because its letters are many, ikhfāʾ is the most frequent of the four rulings — mastering its ghunnah is a clear sign of a skilled reciter.
How to Master These Rules in Practice
Tajwīd is learned by ear before books: the rule is understood from pages, but correct pronunciation is only fixed by reciting to a qualified teacher who listens and corrects you on the spot. In our circles we begin with these rules precisely because they recur in nearly every verse, so the ruling settles through repeated practice rather than theory alone.
- Read one page of the muṣḥaf daily and mark every occurrence of the four rulings before reciting it.
- Listen to a skilled reciter and repeat after him, tracking the ghunnah and its length.
- Recite to a teacher or proficient peer and ask for immediate correction.
- Review the theory after practice, not before, so the sound binds to the rule in your ear.
The Messenger of Allah ﷺ said: "The best of you are those who learn the Qur'an and teach it" [al-Bukhārī]. Congratulations on a path that begins with learning the Book of Allah and perfecting its recitation. What feels heavy at first will, with sincere practice, become second nature. May Allah grant us all recitation of His Book as it was revealed, and make us among the people of the Qur'an — the people of Allah and His elect.