Stacked Vowels: ิ ี ึ ื ั ุ ู

June 14, 20262 min readVowelsFundamentals

See these keys on the full keyboard layout

Seven of Thai's most common vowels do not sit on the same horizontal line as the consonant they belong to. Instead they stack: ิ ี ึ ื ั appear above the consonant, while ุ and ู descend below it. On screen a syllable like กิ shows the ิ floating over the ก, but on the keyboard you press ก first, then ิ — the display is vertical but the input remains left-to-right. Understanding this distinction between rendering position and input order is the conceptual hurdle for this skill.

Why it matters

Stacked vowels are extraordinarily common. Sara ii (ี) appears in words like ดี, มี, ปี, ที, นี้ — everyday words you will type constantly. Sara i (ิ) gives the short /i/ sound in คิด, จิต, ริม, and many others. Mai han akat (ั) is the short /a/ that precedes nasal endings in กัน, ฉัน, มัน, and สั้น. The below-the-line vowels ุ and ู provide the short and long /u/ sounds: ทุ, คุ, รู, หู. Without these seven vowels you cannot write a representative Thai sentence.

The characters

Kedmanee positions these vowels as follows. Above-the-consonant: ั on Y (top row, right index), ี on U (top row, right index one step right), ึ on Digit7 (number row, right index reaching up), ื on N (bottom row, right index), ิ on B (bottom row, left index). Below-the-consonant: ุ on Digit6 (number row, right index), ู on Shift+Digit6. A notable pattern: the right index finger is responsible for ั (Y), ี (U), ุ (Digit6), and ึ (Digit7) — four of the seven stacked vowels. Training this one finger precisely pays outsized dividends.

Technique

  • Always type the consonant before the stacked vowel, even though the vowel renders above or below it. The operating system's Thai input engine handles the visual stacking; your job is the keystroke sequence.
  • For ู (Shift+Digit6), press the left Shift with your left hand while your right hand types Digit6 — using the opposite hand's Shift from the character key keeps both presses comfortable.
  • When drilling ิ (B, bottom-left index) back-to-back with ี (U, top-right index), feel the full diagonal contrast: one finger moves down-left, the other up-right. Exaggerating the contrast early prevents later confusion.

Common mistakes

The most common confusion is between ิ (B, bottom-left) and ี (U, top-right). They look similar — both thin vertical strokes above the consonant, the only difference a length mark on the latter — and they are typed on completely opposite sides of the keyboard. A second frequent error is pressing Digit6 for ุ and realising too late that the Shift key was held, producing ู instead. Add a brief pause before any Shift+number reach to confirm the Shift state. Finally, ื (N, bottom row, right index) is often confused with ิ — verify with your heatmap which of the two is lagging.

Start practising →

Related guides