Kedmanee is the layout printed on virtually every Thai keyboard — a 1931 design that gave the most frequent Thai characters the unshifted keys and pushed the rare ones onto the Shift layer. Below is the full arrangement, the frequency logic behind it, and how it saw off a scientifically superior rival.
Unshifted keys carry the frequent characters — including the number row, which types Thai letters and vowels rather than digits. Shift (the small corner characters) reaches the rare consonants, the Thai numerals ๑–๙, and the baht sign ฿. The obsolete letters ฃ and ฅ survive together on a single key at the right edge.
The Kedmanee layout solves a hard packing problem: Thai has 44 consonants, more than a dozen vowel symbols, four tone marks, and its own numerals — far more characters than a keyboard has keys. Its answer was frequency. The characters Thai text uses constantly — consonants like ก, น, and ร, vowels like า, ี, เ, and แ, and the two common tone marks ่ and ้ — sit on the unshifted layer, while rare consonants such as ฎ, ฐ, and ฌ wait behind Shift.
The most striking consequence is the number row. Unshifted, it types Thai consonants and vowels — ภ, ถ, ค, ต, จ, ข, ช, plus the vowels ุ and ึ — because letters mattered more than digits. Thai numerals ๑–๙ are present, but only on the Shift layer, and Western digits are not on the Thai layer at all: typing 123 means toggling to the Latin layout or reaching for the numpad.
Standardized by the Thai Industrial Standards Institute as TIS 820 — the current revision is TIS 820-2538, issued in 1995 — Kedmanee is the default Thai layout on Windows, macOS, Linux, Android, and iOS. Physical keyboards sold in Thailand are always dual-printed, Thai characters sharing every keycap with Latin QWERTY, and typists flip between the two layers dozens of times a day.
Thailand's first typewriter came in the 1890s, when Edwin Hunter McFarland adapted a Smith Premier machine to Thai — and, unable to fit the whole alphabet, famously left off the consonants ฃ and ฅ, hastening their slide into obsolescence. The layouts of those early machines were workable but ad hoc.
In 1931 Suwanprasert Ketmanee rearranged the Thai keyboard around a frequency analysis of the language, producing the design that still carries his surname (also romanized Kedmanee). It spread with the machines, survived the jump to computers unchanged, and was eventually codified by the Thai Industrial Standards Institute as TIS 820, most recently revised as TIS 820-2538 in 1995.
It faced one serious challenger: the Pattachote layout, designed in the 1960s from fresh efficiency studies and later endorsed by Thai research as measurably faster. It did not matter. Kedmanee's installed base of trained typists and printed keycaps proved unbeatable — Thailand's own rerun of the QWERTY-versus-Dvorak story.
Because Thai needed the keys more than the digits did. With 44 consonants plus vowels and tone marks to place, Kedmanee assigned the unshifted number row to frequent letters like ภ, ถ, ค, ต, จ, ข, and ช. Thai numerals ๑–๙ moved to the Shift layer, and Western digits vanished from the Thai layer entirely — Thai typists switch to the Latin layer or use the numpad for them.
Kedmanee is the 1931 standard everyone actually uses; Pattachote is a 1960s challenger rearranged from newer frequency studies, and research found it genuinely more efficient — less finger travel, better hand balance. It still lost: by then Thailand's typists, schools, and machines were all committed to Kedmanee. Operating systems continue to offer Pattachote as an option for a small community of enthusiasts.
Always. Physical keyboards sold in Thailand are dual-printed, with Thai and Latin characters sharing every keycap, because Thai computing constantly mixes the two — URLs, email addresses, and Western digits all require the Latin layer. A single shortcut or toggle key flips between the layouts, and Thai typists use it reflexively.
Two consonants (kho khuat and kho khon) that modern Thai no longer uses — dictionaries replaced them with ข and ค decades ago, a decline that began when the first Thai typewriter left them off in the 1890s. The Kedmanee standard still reserves a key for the pair, so every Thai keyboard faithfully carries two letters almost nobody types.
Yes — the free AnyKeyboard Thai keyboard linked below runs the exact layout in the diagram in your browser. Click the keys or type on your own keyboard, use Shift to reach the rare consonants and Thai numerals, then copy the text anywhere. It is an easy way to explore the layout before installing it system-wide.