Thai script summary

Updated 13-Jan-2018 • tags thai, scriptnotes

This page provides basic information about the Thai script. It is not authoritative, peer-reviewed information – these are just notes I have gathered or copied from various places as I learned. For similar information related to other scripts, see the Script comparison table.

Clicking on red text examples, or highlighting part of the sample text shows a list of characters, with links to more details. Click on the vertical blue bar (bottom right) to change font settings for the sample text.


ข้อ 1 มนุษย์ทั้งหลายเกิดมามีอิสระและเสมอภาคกันในเกียรติศักด[เกียรติศักดิ์]และสิทธิ ต่างมีเหตุผลและมโนธรรม และควรปฏิบัติต่อกันด้วยเจตนารมณ์แห่งภราดรภาพ

ข้อ 2 ทุกคนย่อมมีสิทธิและอิสรภาพบรรดาที่กำหนดไว้ในปฏิญญานี้ โดยปราศจากความแตกต่างไม่ว่าชนิดใด ๆ ดังเช่น เชื้อชาติ ผิว เพศ ภาษา ศาสนา ความคิดเห็นทางการเมืองหรือทางอื่น เผ่าพันธุ์แห่งชาติ หรือสังคม ทรัพย์สิน กำเนิด หรือสถานะอื่น ๆ อนึ่งจะไม่มีความแตกต่างใด ๆ ตามมูลฐานแห่งสถานะทางการเมือง ทางการศาล หรือทางการระหว่างประเทศของประเทศหรือดินแดนที่บุคคลสังกัด ไม่ว่าดินแดนนี้จะเป็นเอกราช อยู่ในความพิทักษ์มิได้ปกครองตนเอง หรืออยู่ภายใต้การจำกัดอธิปไตยใด ๆ ทั้งสิ้น

Usage & history

From Scriptsource:

The Thai script is used primarily for writing the Thai language, as well as Northern Thai, Northeastern Thai, Southern Thai, and Thai Song, which are separate languages. It is also used to write a number of minority languages in Thailand, Laos and China, as well as Pali, which is widely used in Buddhist temples and monasteries. Both the Thai language and script are closely related to Laotian. The script is of Indic origin, derived from Old Khmer.

From Wikipedia:

Thai alphabet (Thai: อักษรไทย; RTGS: akson thai; [ʔàksɔ̌ːn tʰāj]) is used to write the Thai, Southern Thai and other languages in Thailand. ...

The Thai alphabet is derived from the Old Khmer script (Thai: อักษรขอม, akson khom), which is a southern Brahmic style of writing derived from the south Indian Pallava alphabet (Thai: ปัลลวะ).

Thai is considered to be the first script in the world which invented tone markers to indicate distinctive tones, which are lacking in the Mon-Khmer (Austroasiatic languages) and Indo-Aryan languages from which its script is derived. Although Chinese and other Sino-Tibetan languages have distinctive tones in their phonological system, no tone marker is found in their orthographies. Thus, tone markers are an innovation in the Thai language that later influenced other related Tai languages and some Tibeto-Burman languages on the Southeast Asian mainland.

Thai tradition attributes the creation of the script to King Ramkhamhaeng the Great (Thai: พ่อขุนรามคำแหงมหาราช) in 1283, though this has been challenged.

Key features

Thai is an abugida. Consonant letters have an inherent vowel sound. Vowel-signs are attached to the consonant to produce a different vowel. See the table to the right for a brief overview of features, taken from the Script Comparison Table.

Unlike devanagari, multiple vowel-signs may be used with a single character, and those positioned to the left of the consonant(s) are not combining characters.

Like indic scripts, thai is based on orthographic syllables, so the vowel-sign is actually attached to the syllable. An orthographic syllable includes clusters of consonants without intervening vowel sounds. These clusters are typically represented as partially merged forms, called conjuncts.

Text is written horizontally, left to right.

Character lists

The Thai script characters in Unicode 10.0 are contained in a single block (not counting shared characters, such as punctuation):

Follow these links for information about characters used by languages associated with this script. The numbers in parentheses are for non-ASCII characters.

For character-specific details see Thai character notes.

Combining characters

Most of the combining characters in Thai are used for vowel-signs and tone marks.

Thai regularly combines multiple combining characters above a base consonant. There are two examples in the text below, both of which show a base character with a vowel sign and then a tone mark on top.


Multiple diacritics (vowel sign + tone mark) attached to the same base character.

Context-based positioning

Combining characters need to be placed in different positions, according to the context. The example below shows the same tone character displayed at different heights, according to what falls beneath it.


The same tone mark displayed at different heights.


Thai has a set of digits, that are used regularly.

list all

Text layout

Word separators

Thai words are not separated by spaces or any other character, within a phrase. Spaces do have a function in Thai text, but it is to separate phrases or sentences – they are the equivalent of the comma or period. Although the boundaries are not demarcated, there is a concept of words in the text, for example, lines are supposed to be broken at word boundaries.


Word boundaries occur where the vertical lines appear, though they are not marked by the script.

text delimiters

Thai uses standard Latin punctuation, but deviates significantly in its use of space as a phrase marker, rather than a word separator. This means that it doesn't normally use comma or full stop characters.

Line breaks & text wrap

Thai doesn't indicate word boundaries, but when Thai text is wrapped at the end of a line you should not split a word. This normally requires an application to look up in a dictionary where the word boundaries fall. As you change the width of the browser window the highlighted text above should break at the following points if you browser supports Thai wrapping:



Justification in Thai adjusts blank spaces, but also makes certain adjustments to inter-character spacing. Browsers currently tend not to justify Thai text well.

Use the control below to see how your browser justifies the text sample here.

ทุกคนเสมอกันตามกฏหมายและมีสิทธิที่จะได้รับความคุ้มครองของกฏหมายเท่าทียมกัน โดยปราศจากการเลือกปฏิบัติใด ๆ ทุกคนมีสิทธิที่จะได้รับความคุ้มครองเท่าเทียมกันจากการเลือกปฏิบัติใด ๆ อันเป็นการล่วงละเมิดปฏิญญา และจากการยุยงให้เกิดการเลือกปฏิบัติดังกล่าว

Line height

Thai places vowel and tone marks above base characters, one above the other, and can also add combining characters below the line. The complexity of these marks means that the vertical resolution needed for clearly readable Thai text is higher than for, say, Latin text. In addition, Thai tends to adds more interline spacing than Latin text does.

Here is an example of a word with combining characters above and below base characters:


Multiple diacritics above and below the base significantly increase the vertical height of lines.
Last changed 2018-01-13 14:17 GMT.  •  Make a comment.  •  Licence CC-By © r12a.