Every Hebrew letter has at least one Arabic descendant of the same ancient ancestor. Where a row shows two Arabic letters, Hebrew merged two sounds that Arabic kept apart — those are the “extra” letters, and they are the only truly new thing to learn. Tap any Arabic letter to open its details.
ا alif · ā Alef and alif are the very same Phoenician ox-head letter — both head their alphabets and both open the word for father: אב/أَب.
ب ba · b A perfect one-to-one match — בית/بَيْت (house) is the word both letters are literally named after.
ج jim · j Gimel and jīm are one letter — Arabic's ancient hard g softened into j (Egyptians still say g): גמל/جَمَل (camel).
د dal · d Dalet to dāl, one-to-one: דם/دَم (blood) and דוב/دُبّ (bear).
ه ha (soft) · h He to hāʾ: הוא/هُوَ (he) is a perfect match, and Hebrew's ה־ definite article plays the same role Arabic gives to ال-.
و waw · w Identical letter, identical job: the prefix ו־ (and) is Arabic وَ- (and), and Biblical vav was pronounced w exactly as و still is.
ذ dhal · dh Hebrew folded this dh sound into ז — gold is זהב/ذَهَب and a wolf is זאב/ذِئْب. ز zay · z The straightforward zayin match: זית/زَيْتُون (olive) and זרע/زَرْع (seed, crop).
ح ḥa · ḥ This is the original pharyngeal ḥet, still preserved in Mizrahi Hebrew: חלב/حَلِيب (milk), חמור/حِمَار (donkey). خ kha · kh Hebrew merged ح and خ into a single ח — and ironically, modern Israelis pronounce ח exactly like خ: חמש/خَمْسَة (five).
ط ṭa · ṭ Tet began life as exactly this emphatic ṭ — hear it in טוב/طَيِّب (good) and טבח/طَبَّاخ (cook).
ي ya · y Yod to yāʾ: יד/يَد (hand) and יום/يَوْم (day) are letter-for-letter twins.
ك kaf · k Kaf to kāf, no surprises: כלב/كَلْب (dog) and כתב/كَتَبَ (he wrote).
ل lam · l Lamed to lām: לשון/لِسَان (tongue) and לילה/لَيْلَة (night) line up letter for letter.
م mim · m Mem to mīm: מלך/مَلِك (king) and מים/مَاء (water) — both letters descend from the same ancient wavy-water sign.
ن nun · n Nun to nūn, same name and all: נהר/نَهْر (river) and נפש/نَفْس (soul).
ع ʿayn · ʿ The same letter through and through — both names literally mean 'eye', and the word is a perfect cognate: עין/عَيْن. غ ghayn · gh Hebrew merged gh into ע — that is why Gaza is עזה but Arabic says غَزَّة (Ghazza), and a raven is עורב/غُرَاب.
ف fa · f Semitic p softened to f in Arabic, so פ pairs with ف: נפש/نَفْس (soul) — and even פול/فُول (fava bean), an ancient food word the two languages share.
ص ṣad · ṣ Hebrew צ was originally this emphatic ṣ, not 'ts': fasting is צום/صَوْم, and a bird is צפור... or in Arabic, عُصْفُور. ض ḍad · ḍ Hebrew merged ḍ into צ — that is why land is ארץ/أَرْض and laughing is צחק/ضَحِك. ظ ẓa · ẓ A third ancient sound Hebrew squeezed into צ: noon is צהריים in Hebrew and ظُهْر in Arabic.
ق qaf · q The historic deep qof that Hebrew moved forward to a plain k: קרוב/قَرِيب (near), קבר/قَبْر (grave).
ر ra · r Resh to rāʾ: ראש/رَأْس (head) and רוח/رِيح (wind) share the same skeleton.
ث tha · th Hebrew merged this th sound into ש — that is why three is שלוש in Hebrew but ثَلَاثَة in Arabic, and garlic is שום/ثُوم. س sin · s In cognates س almost always answers Hebrew ש — שלום/سَلَام, שנה/سَنَة — even though in the alphabet it sits in samekh's (ס) historical slot.
שׂ sin (left-dotted)
1 Arabic letter
ش shin · sh Arabic ش historically answers Hebrew שׂ (the left-dotted sin): עשר/عَشْرَة (ten) and שֵׂעָר/شَعْر (hair).
ت ta · t Plain tav to plain tāʾ, one-to-one: תמר/تَمْر (date) and תחת/تَحْت (under).