Nun Sakinah and Tanwin Rules, Explained Simply
Learn the four nun sakinah and tanwin rules in tajweed: izhar, idgham, iqlab and ikhfa, with Qur'an examples, letter lists and memory aids for beginners.
You are reciting smoothly, then you hit a nun with a small circle over it, or a word ending in two fathas, and you freeze. Do you say the sound clearly? Merge it into the next letter? Turn it into something else entirely? Every reciter has stumbled here, because this one letter and this one vowel pattern change their sound more than almost anything else in the Qur'an. The good news is that what feels like guesswork is actually a closed system with only four possible outcomes, and each one is decided by a single question: which letter comes immediately after? Once you can answer that question, you already know the rule. This article walks through all four, with a real ayah for each one you can find and listen to.
What nun sakinah and tanwin actually are
A nun sakinah is simply the letter ن carrying a sukoon, no vowel of its own, so it is pronounced as a plain "n" sound with nothing after it. Tanwin is the pair of extra strokes you see at the end of some words, doubled fatha, doubled kasra or doubled damma, and it adds that same "n" sound to the end of the word even though there is no written nun there at all.
كِتَابٌ
kitaabun
a book
The doubled damma (ـٌ) at the end is tanwin. It is not written as a letter, but it is pronounced as an extra "n" sound: kitaab-un. For every rule in this article, that unwritten "n" behaves exactly like a written nun sakinah.
Because tanwin and nun sakinah produce the identical sound, they are governed by identical rules, and tajweed teachers always treat them as one topic. What happens to that "n" sound (spoken clearly, merged, converted or hidden) depends entirely on the very next letter the reciter meets, whether that letter starts a new word or, in a small number of cases, continues within the same word.
“The one who is skilled in reciting the Qur'an will be with the honourable and obedient scribes (the angels), and the one who recites the Qur'an and finds it difficult, doing their best with it, will have two rewards.”
That hadith is worth holding on to while you work through these rules. Precision matters, and it is worth the effort, but the Prophet ﷺ promised a reward for the reciter who finds it hard and keeps trying, not only for the one who finds it easy. These four rules are a tool for getting closer to fluent, correct recitation, not a bar you must clear before your recitation counts.
The four rules at a glance
| Rule | Letters | What you do |
|---|---|---|
| Izhar (clear) | ء ه ع ح غ خ | Pronounce the nun or tanwin sound clearly, with no hum and no merging. |
| Idgham with ghunnah | ي ن م و | Merge the nun into the next letter and hold a nasal hum for roughly two counts. |
| Idgham without ghunnah | ل ر | Merge the nun fully into the next letter, doubling it, with no hum at all. |
| Iqlab | ب | Convert the nun sound into a light meem sound before pronouncing the ba. |
| Ikhfa (hidden) | ص ذ ث ك ج ش ق س د ط ز ف ت ض ظ | Hide the nun between clear and merged, with a light nasal hum, while your mouth shapes for the next letter. |
Between them, those five letter groups (six, six, one and fifteen) account for every letter of the Arabic alphabet, so every single nun sakinah or tanwin you meet falls under exactly one of these four rules. Nothing is left over and nothing overlaps. The rest of this article takes each rule in turn.
Izhar: pronouncing the nun clearly
Izhar means "clarity" or "showing plainly", and it is the default rule: when a nun sakinah or tanwin is followed by one of six throat letters, you simply say the "n" sound cleanly, exactly as it is written, with no hum and no blending into what comes next. These six letters sit so far back in the throat, away from the tip of the tongue where the nun itself is made, that there is no natural overlap for the sound to merge into.
ء ه ع ح غ خ
hamzah, ha, 'ayn, ha, ghayn, kha
The six throat letters, taught in three pairs from deepest in the throat to nearest the mouth.
Deep throat: hamzah (ء) and ha (ه). Middle of the throat: 'ayn (ع) and ha (ح). Near the mouth: ghayn (غ) and kha (خ). Each pair is articulated close together, which is exactly why they are taught as pairs rather than a random list of six.
وَلَمْ يَكُن لَّهُ كُفُوًا أَحَدٌ
“Nor is there to Him any equivalent.”
Idgham: merging into the next letter
Idgham means "merging", and it happens when a nun sakinah or tanwin is followed by one of six letters that spell the Arabic word يرملون (yarmaloon, "they run"): ي ر م ل و ن. Rather than being pronounced as a separate sound, the nun disappears and blends directly into the letter after it. There are two distinct versions, depending on which of those six letters is doing the merging.
Idgham with ghunnah
When the merging letter is ya, nun, meem or waw, the merge keeps a nasal hum (ghunnah) running for roughly two counts. You can hear the nun's sound survive as that hum even though the letter itself has gone.
ي ن م و
ya, nun, meem, waw
The four idgham-with-ghunnah letters, remembered as "yanmoo".
Say the word yanmoo (يَنْمُو) to hold all four in order: ya, nun, meem, waw.
وَمِنَ النَّاسِ مَن يَقُولُ آمَنَّا بِاللَّهِ وَبِالْيَوْمِ الْآخِرِ وَمَا هُم بِمُؤْمِنِينَ
“And of the people are some who say, "We believe in Allah and the Last Day," but they are not believers.”
Idgham without ghunnah
When the merging letter is lam or ra, there is no hum at all. The nun sound vanishes completely and the following letter is simply pronounced doubled, as if it carried a shaddah.
ل ر
lam, ra
The two idgham-without-ghunnah letters.
The nun sound disappears entirely into the lam or ra, with no nasal sound left behind at all, unlike idgham with ghunnah.
أُولَـئِكَ عَلَى هُدًى مِّن رَّبِّهِمْ وَأُولَـئِكَ هُمُ الْمُفْلِحُونَ
“Those are upon [right] guidance from their Lord, and it is those who are the successful.”
Iqlab: turning the sound into a hidden meem
Iqlab means "conversion", and it has only one trigger letter: ba. When a nun sakinah or tanwin is followed by ba, the nun sound is converted into a light meem sound (with ghunnah) before the ba is pronounced. Meem and ba are both made with the lips closed, so the conversion lets the sound flow smoothly into the ba instead of forcing an awkward jump from the tongue to the lips. The scribes of the Uthmani mushaf mark this rule with a small meem written above the letter, so you can often see iqlab coming before you even reach it.
ب
ba
The only iqlab letter.
Iqlab can happen between two words or, less commonly, inside a single word, as in the example ayah below.
قَالَ يَا آدَمُ أَنبِئْهُم بِأَسْمَائِهِمْ
“He said, "O Adam, inform them of their names."”
Ikhfa: hiding the sound between the two
Ikhfa means "hiding", and it covers everything left over: fifteen letters that are neither the six throat letters, nor the six yarmaloon letters, nor ba. When a nun sakinah or tanwin meets one of these, you do not pronounce it clearly and you do not merge it away. Instead, the tip of the tongue rests near the nun's own articulation point without fully touching it, while the rest of the mouth already begins shaping the next letter, and a light nasal hum carries the sound for roughly two counts.
ص ذ ث ك ج ش ق س د ط ز ف ت ض ظ
sad, dhal, tha, kaf, jeem, sheen, qaf, seen, dal, taa, za, fa, ta, dad, dha
The fifteen ikhfa letters: everything remaining once the throat letters, the yarmaloon letters and ba are accounted for.
This is by far the largest of the four groups, which is exactly why beginners meet ikhfa the most often in ordinary recitation.
مَن ذَا الَّذِي يَشْفَعُ عِندَهُ إِلَّا بِإِذْنِهِ
“Who is it that can intercede with Him except by His permission?”
The mistakes that give beginners away
Do
- Treat tanwin exactly like a written nun sakinah. The rule depends on the sound, not on whether a nun letter is actually written.
- Listen closely to a reciter you trust for each rule before you try to reproduce it yourself.
- Hold the ghunnah in idgham with ghunnah and in ikhfa for a similar, steady length each time, not a rushed flick or an exaggerated hum.
- Check the actual letter that follows, every time, rather than guessing a rule from memory or from a translation.
Don’t
- Don't merge a nun sakinah with a yarmaloon letter that happens to fall inside the very same word, as in bunyaan or dunya. That case takes izhar, not idgham.
- Don't add any hum to izhar. It is meant to sound completely clean.
- Don't strip the hum out of idgham with ghunnah or out of ikhfa, or hold it so long that it turns into a separate syllable.
- Don't pronounce iqlab as a full stopped "b" sound. It becomes a light meem with ghunnah, not a hard stop.
How to practise the four rules properly
A simple practice routine
- 1
Learn the letters, not just the labels
Write out the six izhar letters and the six idgham letters split into their two groups, plus the single iqlab letter. Everything else you meet is ikhfa, by elimination.
- 2
Pick one ayah per rule
Use the examples in this article, or find your own with the search on quran.com, and listen to a trusted reciter say each one several times before you repeat it back.
- 3
Record yourself and compare
A short voice recording is enough to hear whether your ghunnah is too short, too long, or missing entirely, which is very hard to judge while you are reciting.
- 4
Ask a teacher to check specifically for this
Ghunnah length and mouth shape are genuinely difficult to self-correct. A teacher listening live can flag the exact moment a rule slips.
- 5
Review a little, often
A few focused minutes a day across a week will fix these rules more reliably than one long session.
Correct tajweed is not decoration on top of the words of Allah. It is part of how those words were revealed and how they have been carried, letter for letter, ever since.
Where nun sakinah and tanwin fit in your wider tajweed
These four rules build directly on the makharij, the articulation points of every Arabic letter. If you have not read our guide to where every Arabic letter is born, it is worth reading first, since izhar, idgham, iqlab and ikhfa only make sense once you can feel where each letter is actually produced. Once you are comfortable with nun sakinah and tanwin, the natural next stop in tajweed is learning where to stop and start reciting, and if you are weighing up how to structure your learning from here, our guide to what a good online tajweed course covers walks through what to look for. None of this replaces real, live correction, though. If you want feedback on your ghunnah and your letters in real time, you can find a Qur'an teacher who will listen rule by rule and correct you as you go.
Key takeaways
- Nun sakinah (ن with sukoon) and tanwin (the doubled end vowels) produce the same "n" sound and follow the same four rules.
- Izhar is pronounced clearly before the six throat letters: ء ه ع ح غ خ.
- Idgham merges the nun into ي ن م و with a hum, or into ل ر with no hum at all, unless the letter falls inside the same word.
- Iqlab converts the nun into a light meem sound before ب, and ikhfa hides it with a light hum before the remaining fifteen letters.
- Learning the letter groups by heart, then listening and practising against real ayat, is far more effective than memorising rule names alone.
Further reading
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