Greek Accents on a Mac: Tonos, Dialytika and the Key That Types Nothing

You switched your Mac to the Greek input source. You press the key to the right of L, expecting a semicolon, and nothing happens — no character, no beep, nothing at all. Then you press α and get ά.

Nothing you did was wrong, and nothing is broken. If you want the whole of it — every mark, every codepoint, and the handful of places this layout does something you would not guess — that is what follows. And if you came to learn the layout rather than decode it, Mochi Type teaches Greek touch typing on this exact arrangement.

Apple’s own help page on accent marks explains the mechanism exactly once, with a Latin example: to enter ã using the ABC layout, press Option-N to enter a tilde, then press the a key. The page never mentions Greek, tonos, dialytika or the dialytika-tonos. So here is the Greek half.

Key positions below are given as the letters printed on a US keyboard, because that is where your fingers are — a Greek keyboard prints Greek legends on the same physical keys. (Everything was read out of macOS’s own keyboard layout data on 26.6, key code by key code, modifier by modifier, with real two-key sequences fed back in.)

The three dead keys

You have already met one of them. Press, get nothing, press a vowel, get the accented letter. There are three such keys on the Greek layout, and they are not scattered about the keyboard — they are the same physical key under three different modifiers.

None of them produces anything when pressed alone. That silence is the entire point of a dead key: macOS is holding the mark and waiting to see what you type next.

Here is exactly what each one holds:

Press	Glyph	Codepoint	Unicode name
; (right of L)	΄	U+0384	GREEK TONOS
Shift + ;	¨	U+00A8	DIAERESIS
Option + ;	΅	U+0385	GREEK DIALYTIKA TONOS
Shift + W	΅	U+0385	GREEK DIALYTIKA TONOS

One physical key carries all three. The fourth row is a duplicate: on the key at the physical W position — the one that types the final sigma ς — Shift gives you the same dialytika-tonos that Option and the semicolon key give you. Two routes, identical output.

What the tonos key makes

This is the one you will use all day. It is the plain accent, the one that turns up in nine Greek words out of ten, and it is always this key: press it, nothing happens, press the vowel, and the accented letter appears on the second press.

Press ΄, then a vowel:

Sequence	Result	Codepoint
΄ then α	ά	U+03AC
΄ then ε	έ	U+03AD
΄ then η	ή	U+03AE
΄ then ι	ί	U+03AF
΄ then ο	ό	U+03CC
΄ then υ	ύ	U+03CD
΄ then ω	ώ	U+03CE

Hold Shift on the second press and you get the capital. All seven work: Ά U+0386, Έ U+0388, Ή U+0389, Ί U+038A, Ό U+038C, Ύ U+038E, Ώ U+038F.

Each of those is one codepoint, not a letter followed by a combining accent. macOS emits the precomposed character directly. If you have ever pasted Greek into a search field and had it fail to match, that is worth knowing: ά from this keyboard is U+03AC, a single character, and it will not equal an α followed by U+0301 that came from somewhere else.

The dialytika, and the one that carries both marks

The other two dead keys are far narrower than the accent. One arms the two dots on their own; the other arms the two dots and the accent as a single mark, not as two marks applied one after the other. One composes with exactly four letters, the other with exactly two, and that is the whole of what they will do — there is no long list to memorise here.

Try them on your own Mac: hold the modifier, press the semicolon key, then press the letter. Shift with the semicolon key arms the plain diaeresis, U+00A8. It composes with exactly four letters:

¨ then ι  →  ϊ  U+03CA
¨ then υ  →  ϋ  U+03CB
¨ then Ι  →  Ϊ  U+03AA
¨ then Υ  →  Ϋ  U+03AB

Option with the same key — or Shift with the W-position key — arms U+0385, which carries the diaeresis and the accent together. It composes with two letters and nothing else:

΅ then ι  →  ΐ  U+0390
΅ then υ  →  ΰ  U+03B0

Two marks, one dead key, one resulting codepoint. There is no version of this where you type the dialytika and then add the tonos on top.

When the composition does not exist

So what happens if you arm the accent and then press a consonant, or a space, or the accent key again? Nothing bad. You do not lose the keystroke, and the keyboard does not get stuck holding a mark you no longer want.

A dead key followed by a letter it cannot combine with does not fail silently and does not eat your keystroke. macOS flushes the mark and then types the letter.

Check it yourself — these are the three cases:

΄ then κ      →  ΄κ      U+0384 U+03BA   mark released, keyboard back to normal
΄ then space  →  ΄       U+0384          mark released, keyboard back to normal
΄ then ΄      →  ΄       U+0384          mark released — and immediately re-armed

The space route is how you type a bare tonos on purpose. A lone U+0384 is otherwise unreachable on this layout: the key never emits it on the first press, and no other key on any modifier layer carries it.

The third line looks like it does the same job, and it does not. Pressing the tonos key twice emits one U+0384 — and leaves the dead key armed again. Type α next and you get ΄ά, not ΄α. The same is true of the other two: Shift-; twice arms the diaeresis again, Option-; twice arms the dialytika-tonos again. Use space.

The semicolon is not missing, it moved

If you went looking for a broken layout, this is usually the reason: the semicolon key stopped producing a semicolon. Nothing is broken. Two things explain it, and neither is a fault.

Greek uses the semicolon as its question mark — the erotimatiko. And since the tonos took the semicolon’s key, the semicolon had to go somewhere.

It went to the physical Q position:

Press	Character	Codepoint
Q	;	U+003B
Shift + Q	:	U+003A
Option + Q	·	U+00B7

That third row is the ano teleia, the Greek raised point that does the job of a semicolon in a Greek sentence. Note the codepoint: macOS emits U+00B7 MIDDLE DOT, not U+0387 GREEK ANO TELEIA. The two are canonically equivalent in Unicode, but they are different bytes, and a byte-exact search will tell them apart.

Shift with the slash key still produces ? U+003F on the Greek layout — the key is there, it is just not what Greek prose uses. A Greek question ends with ;.

There is a second way to reach the accented vowels

If an accented vowel has ever appeared when you did not touch the accent key, that was not a glitch either. Some of the accented letters also sit on keys of their own, one press each, on the Option-Shift layer.

It looks like the easier road. It is not — but it is worth seeing, if only so it stops surprising you.

The Greek layout also puts seven precomposed tonos vowels on the Option-Shift layer as ordinary single keys, no dead key involved:

Press	Result
Option-Shift + A	ά
Option-Shift + 1	έ
Option-Shift + 2	ί
Option-Shift + 3	ή
Option-Shift + 4	ό
Option-Shift + 0	ύ
Option-Shift + .	ώ

Six more sit on the same layer, scattered:

Press	Result
Option-Shift + V	Ά
Option-Shift + E	Έ
Option-Shift + N	Ό
Option-Shift + M	Ύ
Option-Shift + 5	Ώ
Option-Shift + G	Ϊ

These are real single keystrokes and they produce exactly the same codepoints. They are also a worse thing to memorise: the assignment follows no pattern, and it is incomplete. Between them the three dead keys reach twenty accented letters; the Option-Shift layer carries thirteen of those, and the seven it misses are Ή, Ί, Ϋ, ϊ, ϋ, ΐ and ΰ. Learn the dead key. The Option-Shift layer is useful mainly as an explanation for why an accented vowel sometimes appears when you did not press the tonos at all.

Polytonic is a different keyboard

Two Greek keyboards ship with macOS, and their names differ by one word. If you are typing modern Greek, you want the plain Greek layout. Polytonic is for classical and pre-1982 orthography.

It is worth checking which one you picked, because the mix-up survives a long time before it bites. The everyday accent behaves the same way on both. What differs is the punctuation around it.

macOS 26.6 ships two Greek layouts, and their identifiers are worth knowing because the names alone do not tell you how far apart they are:

com.apple.keylayout.Greek            Greek
com.apple.keylayout.GreekPolytonic   Greek – Polytonic

On the polytonic layout the key right of L answers with different bytes depending on the route: through Space it gives U+1FFD, the Greek oxia, and cancelled against a non-combining key it drops U+00B4, the Latin acute accent — where the monotonic layout gives U+0384 either way. Several keys that carry ordinary punctuation on the monotonic layout are dead keys for the polytonic accents and breathings instead: the - and = positions become ῏ U+1FCF and ῍ U+1FCD, the [ position becomes ῀ U+1FC0, the ' position becomes ᾽ U+1FBD. The everyday accent behaves identically — ΄ then α gives U+03AC on both — but everything around it has moved, and the two are not interchangeable for anything beyond that.

Drilling the Greek dead keys in Mochi Type

Reading a table is not the same as owning the sequence. Two things make dead keys awkward to practise: the first press gives you no feedback at all, and one key carries all three marks plus a colon, so the modifier is doing all of the discriminating.

Mochi Type handles that with a two-step hint. When the next character is an accented vowel that needs a dead key, the accent key lights first; once you have pressed it, the highlight moves to the vowel. You are shown a sequence in the order you have to press it, rather than a cluster of lit keys to decode.

The accent press itself is not scored. It produces no character, so it cannot be an error and it adds nothing to the keystroke count; it costs you time and not accuracy. And because the app composes the sequence itself before comparing against what you were meant to type, the way you actually reach ά is your business: the dead key and the Option-Shift key both count as correct.

That is the part that matters. If you would rather not read another word about layout tables, you have everything you need.

If you do want the mechanical version: the outline of a hinted key is a solidity gradient in press order — solid on a held Shift, medium dash on the accent, fine dash on the letter — so a three-part sequence like Shift-; then ι reads as three steps rather than three lit keys.

Which one it shows you follows one rule — a character reachable by a single key press is taught on that key, and the dead-key sequence is offered only where nothing direct exists. On the Greek layout that splits the accented vowels in two. For the thirteen letters sitting on the Option-Shift layer the hint points at that key; for Ή, Ί, Ϋ, ϊ, ϋ, ΐ and ΰ it walks you through the dead key, because there is no other way to get them.

The prose Mochi generates for Greek respects the erotimatiko. Everything that runs through the prose punctuation pass — Practice text, the Final Test — ends a Greek question with ; and never with ?, on a Greek-only branch in the sentence generator. The mirror of it matters too: for every other language ; is also thrown in as a soft sentence break that does not start a new capitalised sentence, and on Greek that soft-terminator role is dropped, because there the mark is a question and a question ends a sentence.

One place in the course does not follow that rule, and it is worth knowing before it surprises you. The Learn stage called Punctuation drills the raw set . , ! ? on a dense generator that is language-generic apart from Spanish’s inverted marks, so Greek text in that one stage does contain ?. The stage after next, Extra Symbols, likewise ends every two-to-three-word window with ; in every language including Greek. Both are symbol drills rather than prose — they exist to put the physical key under your finger, and on the Greek layout ? is still Shift and the slash key.

And the limit, because it decides whether any of this is for you: Mochi Type is a typing tutor, not a system utility. It changes no macOS setting, installs no layout and repairs nothing on your Mac. The accents above already work on your machine exactly as described, with nothing installed; what the app adds is the drilling, and only that. The rest of what it does not do is the last section on this page.

Two related pieces sit next door: practising a layout without switching your input source, which explains how a physical-key-code reading makes that possible, and the cheapest-keystroke rule on macOS PolishPro, which is the same idea applied to a layout where a character is reachable several ways.

Where the accents actually turn up

How much of this is worth drilling? Very unevenly. The plain accent is in almost every Greek word you will ever type. The two-dot marks are the opposite — not a single word in Mochi’s smallest Greek word set carries one.

Some honest arithmetic, because it decides how much drilling any of this deserves.

Mochi’s Greek frequency lists are not evenly seasoned with accents. In the smallest set — labelled Top 200, holding 195 words — 185 of them carry a plain tonos, and not one contains a dialytika of any kind. In the largest, 49,540 words, 46,081 carry one of the seven plain-tonos vowels, 216 contain ϊ, 25 contain ϋ, and 30 contain ΐ. The letter ΰ appears in none of the five sets at all, which is presumably why it is the one accented vowel the course never teaches.

So the tonos is not an advanced topic in Greek. It is in nine words out of ten from the first lesson, which is why Mochi’s Greek course introduces ά in the sixth of its eleven letter groups — every language in the app has the same eleven — adds ί, then έ and ό, then ύ and ή over the next three, and closes with ώ, ϊ and ϋ in the tenth and ΐ in the eleventh. The rare mark comes last because it is rare, not because it is hard. (The free tier runs to the fifth of those groups — one short of where ά arrives — so the accents themselves sit on the paid side of the one-time $12.99 unlock.)

What this page does not cover

The Greek support here is one layout. Mochi carries the monotonic Greek arrangement and not the polytonic one, so breathing marks, iota subscript and the rest of the classical apparatus are outside it — those you type in macOS directly, on the layout named above.

Greek also gets the five frequency word sets and nothing else: the movie-quote and book-quote sets exist in seven languages and the misspelled-word sets in ten, and Greek is in neither list. The built-in reading library covers English, German, Russian and Ukrainian only — and only one language’s five books are seeded at a time, the set for whichever language you are currently typing in.

And the accents themselves are macOS’s work, not any app’s. Every sequence in the tables above works in TextEdit, in Mail, in a terminal — anywhere on your Mac, with no software installed. What an app can add is the part where you stop having to think about it — and that part is Mochi Type’s whole job here.