Thai: A Script without Borders

An essay about Thai type design (incl. market overview)

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai

Even though Thailand is one of the top holiday destinations, the fact that the Thai script is used by only around 70 million people makes it a relatively small market in the type design industry. So is it worth the effort researching and designing for the Thai market?

I

set that question aside a long time ago, when I first began experimenting with designing Thai Loop letterforms (Traditional Thai characters are distinguished by small circular loops and are primarily used in school textbooks, the publishing industry, and longer texts). At first, the work felt as if I was dealing with an ampersand in every single letter. From a purely economical perspective, the enormous amount of time and training that Thai type designers invest into the script can rarely be justified.

However, if you measure its value by what it preserves and passes on, then the answer looks very different. If it means that you can prevent historical letterforms from being lost amid technological change and deepen our understanding of the Thai script with every new project… In that case, the answer is always a resounding “Yes!”

Thai type never gets boring. There’s always something to learn, both creatively and technically. Having been born and raised in Bangkok, I have spent the last eight years intensively engaged with our script. In that time, my appreciation for its diversity has steadily grown over time. Every single stylistic variation offers new insights.

As for the historical foundations, however, I’m happy to leave that to the experts: “History of Thai Typography” by Pracha Suveeranont, published by Typotheque, remains to this day, the most comprehensive documentation of the history of Thai typography and print culture. In what follows, I will provide a brief overview and then focus on a few milestones in this history.

An Overview of the Thai Script

The Thai script descends from the family of Brāhmī scripts of India, its most direct predecessor is Old Khmer[^1]. Its formal origin dates back to 1283 and it is traditionally attributed to King Ramkhamhaeng of the Kingdom of Sukhothai. He is said to have adapted the writing system of Old Khmer to Thai phonology. The inscription on which this attribution is based is, however, the subject of scholarly debate[^2].

We read left to right, as in Latin. Our glyph inventory is far smaller than that of many Indic relatives, since Thai abandoned conjunct consonant stacking, yet the system remains complex[^3].

Structurally, the Thai script works fundamentally differently from Western alphabets. Strictly speaking, it isn’t an alphabet at all but an Abugida. At the centre of each syllable sits a consonant sign, which is combined with vowels and other marks. Thai has 44 consonant letters, divided into three classes. In addition to that, there are vowel signs and tone marks. Unlike in Latin, however, these do not simply line up one after another along a baseline. Vowels can stand before, after, above or below a consonant; some vowels even consist of several signs that quite literally enclose a consonant. Thai has no upper- and lowercase letters.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Two-dimensional typesetting: At the centre of a Thai syllable sits a consonant, around which up to three vowel signs and tone marks can be arranged: before, after, above or below it
Two-dimensional typesetting: At the centre of a Thai syllable sits a consonant, around which up to three vowel signs and tone marks can be arranged: before, after, above or below it (Image: Jürgen Siebert)

Tones are part of the writing system as well. Thai distinguishes five spoken tones, yet there is not simply one corresponding sign for each tone. Four diacritical tone marks interact with the class of the given consonant, the length of the vowel and the structure of the syllable.

A tone mark is placed above its consonant and, where necessary, above a vowel sign already sitting there. A single base character can thus be combined with elements to its left, right, above and below. The horizontal sequence we can observe in Latin type becomes a two-dimensional construction. Precisely this fact is a particular challenge for type designers.

In a Latin typeface, letters, diacritics, spacing, and proportions also have to be coordinated with one another. In Thai, however, such combinations are part of the everyday core of the writing system. Vowel signs and tone marks must remain unambiguously assignable across very different sequences of characters, must not collide with each other or with the consonants, and must stay legible even at small sizes.

When a typeface is extended from Extra Condensed to Extra Wide, the available space becomes dramatically limited. We will encounter this problem again later with Neue DIN Thai.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Scanned Thai workbook, from the author’s collection
Scanned Thai workbook, from the author’s collection

Globally, Thai is recognized in two primary styles: Looped and Loopless.

In Thailand, we learn to read and write with looped letterforms. Growing up, Loop was the script of our schoolbooks: formal, familiar, and foundational. Yet outside the classroom, Loopless was everywhere, in advertisements, signage, and product packaging.

To western eyes, it can seem puzzling that Thai readers live with two styles at once. But the division follows its own logic. For long-form reading, especially body text in books, Loop remains the default, while Loopless is preferred for websites, short texts, advertising, and user interfaces.

Recent research by Typotheque[^4] largely confirms this pattern and adds an age dimension. Looped text is strongly recommended for paragraph reading, with its readability advantage holding across all age groups, yet younger readers discern Loopless more easily at small sizes. The authors suggest this reflects Thailand’s typographic landscape, which has been saturated with Loopless since its popularization in the 1990s. In other words, this exposure has trained people’s eyes.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Examples of loopless typefaces in advertising and retail, photographed in 2019
Examples of loopless typefaces in advertising and retail, photographed in 2019
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Thai print advertising dates back to the mid-1800s; loopless display lettering likely rose to prominence around the same time, though exactly when it first appeared in print remains unclear.
Thai print advertising dates back to the mid-1800s; loopless display lettering likely rose to prominence around the same time, though exactly when it first appeared in print remains unclear. — Image: Nawigamune, Anake, comp. “A Century of Thai Graphic Design”. Bangkok: River Books, 2000
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Scanned dry-transfer from author’s collection
Scanned dry-transfer from author’s collection

What makes Thai script particularly complex, for readers and type designers alike, is that this Loop/Loopless distinction sits on top of an already intricate system.

Since Thai has adopted words from Pali and Sanskrit, multiple letters can represent the same sound. Readers simply have to learn which one is used in a particular word. Added to this are character forms that differ only in small details: the loop direction, a small curve, a final stroke. The potential for confusion is correspondingly high.

Towards the end of the 20th century, Thai typeface design underwent a phase of significant simplification, during which many distinctive features were abandoned in favor of a minimalist aesthetic. This trend was particularly pronounced during the era of dry-transfer typefaces.

Today, the trend is moving back in the opposite direction. Details are returning and familiar forms are being revived for Thai readers without sacrificing the flexibility that has always characterized the writing system.

This balance between familiarity and flexibility runs like a common thread through the design projects described below, Pangea Thai and Neue DIN Thai.

Pangea Thai

Pangea by Christoph Koeberlin is a sans serif typeface that falls somewhere between a narrow grotesque and a geometric sans. Overall, it is narrower and thus more space-efficient than a classic geometric sans serif, yet it retains a friendly character through its diagonal terminals and round dots. These qualities, the compactness, the large x-height, and the restrained openness, set the framework that the Thai extension had to respond to.

Designing Thai for Pangea meant designing two styles in one typeface: Looped for Pangea Text and Loopless for Pangea (Display). The process began with the Text variant, since body text is the more conservative and therefore more challenging territory, while display allows greater flexibility. Elements that could be shared across both styles were only selected at the very end.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai
Pangea Thai uses the loopless variant, whereas Pangea Text Thai uses the looped one; the text version features taller ascenders and more generous spacing than the display variant.
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai compared with other typefaces
For the Looped Thai, I chose letterforms with rounded rectangular bottoms, a design with which Thai readers are deeply familiar with.
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai
Pangea Text (Looped) Thai
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai sketches
Pangea sketches with Thai figures, tone marks, and Topatak and Dochada consonants tried out the simplified version.

Pangea Text is designed for comfortable reading at small sizes. For the Looped Thai, I chose letterforms with rounded rectangular bottoms, a design with which Thai readers are deeply familiar with.

They can be found in fonts such as Browallia (designed by: Unity Progress), which became established during the Windows era; in Sarabun (Design: Suppakit Chalermlarp), the standard typeface of Thai government documents; and in Thonburi, the default Thai system font on Apple devices.

To this day, these typefaces shape the image that Thai readers associate with body text in their everyday lives.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai
Similarities between the Latin lowercase g and the Thai versions of the letter So Sua ส
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai
The image is showing the relationship between Thai ascender, at its tails, and descender between the two styles, Loopless and Looped.
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai
The vowel sign Sara Ai Maimalai (ไ) in both Pangea-Thai subfamilies belongs to the signs whose basic form has been preserved in both the looped and loopless styles.

The Pangea Thai project subtly blends traditional and modern forms. Pangea Text Thai seeks to strike a balance between the two: the top of the letters appear more modern, while characters with descenders retain more conservative forms.

This balance also allows the design to keep a close relationship with the loopless style. The goal is to reduce visual clutter as much as possible while ensuring high legibility even in bold weights and small sizes.

When it comes to the proportion and typeface design, it’s about striking a balance with the Latin script. Even minor details of the Latin forms, such as the design of the terminals, have their counterparts in Thai. In Pangea Text, the forms are designed to be slightly more open.

In addition to proportions and overall texture, the characteristic cut-off t of Pangea was also carried over into the Thai versions, in both the Looped and Loopless versions. The angle of their terminals is less steep than in the Latin glyph, so that Thai readers do not find these characters unfamiliar.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai
The angles of the terminals of Soso (ซ) and Chochang (ช) are deliberately less steep than in Pangea Latin so that the characters remain familiar to Thai readers.
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Text Thai
Pangea Text Thai (Looped)
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea Thai
Pangea Thai (Loopless)

Finally, it should be noted that Pangea is an eco-friendly typeface family. 25% of all designer royalties from every purchase is donated to rainforest preservation and to reforestation projects involving local populations (Trees for the Future, The Green Belt Movement and Fairventures Worldwide)[^5].

So, now that Pangea speaks Thai, please take it out into the world. I’m curious to see where the journey leads to.

Try Pangea Thai for free

Neue DIN Thai

Where Pangea asked for subtlety and finesse, Neue DIN asked for endurance: the same script, stretched across widths from XXCondensed to XXWide. Such challenges always force a new, creative solution.

There is always the question of whether Thai can check every box that Latin does in terms of width and weight. The honest answer is that it does not have to. Yet looking back at historical products and printed materials tells a different story: packaging, advertisements, movie posters, and other printed materials from earlier eras displayed remarkable typographic diversity.

Thai script has always shown high flexibility and adaptability, a quality that likely grew out of a long multicultural trading history, with the West as well as with other Eastern cultures. Its letterforms have taken on a wide variety of designs, embracing foreign influences and the style trends of each era. That openness reached beyond trade, as new media found their way to Siam early as well.

From around 1897 onwards, foreign travelling cinema troupes regularly visited Bangkok, at least two to three per year, screening films for the public. This gradually familiarized Siamese audiences with the new entertainment medium, which they came to call “nang farang” (foreign/Western pictures)[^6].

With the cinema posters and with the posters came the typeface designers. The late 1950s and early 1960s in particular were brimming with a spirit of experimentation. Width and line thickness were the least significant variables. Back then, the designers had much more to play with.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek –  From 1900 onwards, Thai cinema developed into a popular form of entertainment that experienced its golden age in the 1930s.
From 1900 onwards, Thai cinema developed into a popular form of entertainment that experienced its golden age in the 1930s.
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – In the mid-20th century, new products, the advertising for them and the accompanying print media brought typographic diversity to Thailand.
In the mid-20th century, new products, the advertising for them and the accompanying print media brought typographic diversity to Thailand.
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek –  Neue DIN Thai
Neue DIN Thai

Over the years, I have continued the research I began in 2019 (see the YouTube video of my presentation at ATypI 2019 in Tokyo) and it consistently confirms the same impression. The technological limitations of later eras have curtailed much of the flexibility that Thai letterforms possessed at that time. At the same time, it is precisely these limitations that have shaped the reading habits that society lives with today.

OpenType features now offer the possibility of gradually regaining some of this flexibility or at least make the once-impossible now possible. Neue DIN Thai is a good example of this, especially in the XXCondensed styles. Narrow typefaces have always been a challenge for Thai because the complex internal shapes of Thai glyphs resist being significantly narrowed. So when it came to developing the Thai version of Neue DIN, which in itself is a classic and rigorously structured typeface that has survived through history, the development of Neue DIN Thai was just as demanding as it was exciting.

Fontwerk’s Neue DIN has been expanded by Andreas Frohloff, Hendrik Weber, and Olli Meier to accommodate today’s digital communication requirements, covering an enormous range of stroke weights and widths. The inner shapes posed a particular challenge. Another challenge was making the Thai tone marks function properly under all these conditions, especially in XXCondensed.

Working alongside Andreas Frohloff made the whole project a privilege and educational experience. His critical eye guided every stage and the reverse-angle italics or Retalic Thai were drawn by him. His comments and feedback came directly, right down to jumping on a video call to talk things through. Even in retirement, he brings decades of experience and shares it generously. There is a great deal to learn from a designer like him and this project proved it many times.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Pangea sketches with Thai figures, tone-marks, and Topatak and Dochada consonants tried out the simplified version.
Two experiments to test the vertical positioning of Thai characters and their tone marks in combinations prone to collisions: the middle tail clearly does not work (Sketch A); the accents in the Latin Neue DIN typeface proved helpful for positioning the tone marks (Sketch B).

In Thai, diacritics are placed both above and below consonants. The position of the tone marks directly affects readability for native speakers. Since tone marks can be combined with all consonants, designers must always take into account how these two groups of characters are combined and function together. The positioning of tone marks in Neue DIN Thai closely follows the positioning of accents in the Latin Neue DIN.

But what happens with tone marks on letters with ascender? Normally, a second set of tone marks is drawn for such characters, known as the Narrow set (.narrow). Narrow means exactly what the name suggests: they are narrower than the default. In Neue DIN Thai, however, especially in the XXCondensed, the Narrow set alone is not enough, since both the spacing between letters and the letter proportions themselves are extremely tight.

Squeezing a tone mark in beside an ascender risks a crash with the tone mark on the previous letter, and the mark itself loses legibility in that position, as seen in Sketch B. To remain legible, one solution is a short-ascender version of Po-pla (ป) that pairs with the top tone mark. This allows the tone mark to move further inward while still remaining unobstructed.

Some letters, like the alternates in these sketches, never made it into the final typeface as they proved impractical in use. But the idea of the shortened ascender idea remained.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Neue DIN Thai
Risk of collision: While the ascender of the “Po-pla” bearing a tone mark must be shortened in the left and right sample words, the mark in the middle word may retain its full height.

In the Latin alphabet, there are some letters with very similar shapes, such as n and h, which differ only in the height of their ascenders. Thai has a comparable pair: Po-pla (ป) and Bo-baimai (บ). If the ascender of Po-pla is shortened too much, the two characters begin to resemble each other.

In practice, it is not feasible to reduce the ascender to a height that falls between the consonant body and the tone mark. This is because the space between the top of the consonant body and the tone mark above it is too narrow to maintain a clearly recognizable distinction between the two characters. Please see the exploration image below.

Therefore, the decision was made to leave the tone marks of the first level at their original height, rather than shifting them upward. If they were raised, the line spacing would have to be increased too much; moreover, characters set too high quickly give the impression that they are floating detached above their base character. So we did not change the tone mark, but fixed Po-pla instead.

For XXCondensed, the best solution ultimately turned out to be deliberately allowing the collision. So, the ascender and the tone mark are permitted to touch. This contact even serves a purpose. It makes it clear that this is a character with an ascender and visually explains why the two forms overlap. As soon as a wider character width provides sufficient space, the Narrow Set is used again. However, this solution applies only to tone marks that can collide with elements above them.

In the illustration “Risk of Collision,” the Po-pla (ป) in the middle word (เป็น) carries the tone mark Mai-taikhu ( ็), which shortens the vowel. In this case, Mai-taikhu is an integral part of the vowel combination (เ- ็), which is the shortened form of the vowel เ-ะ (Sara-e) when followed by a final consonant (น is the final consonant in this example). In this combination, the first part of the vowel, Sara-e (เ), is always written on the baseline, to the left of the main consonant (Po-pla in this case). Since it is itself a vowel, no tone mark is placed above it. As a result, the space above Po-pla on this side (the left side) remains clear (shown in blue). No tone mark belonging to an adjacent letter can come too close to it in this area. This means that Po-pla can retain its original, unmodified shape.

The situation is different for the words on the left and right (see image above). There, a tone mark is located above Po-pla, while at the same time, the character before it has a tall stroke or another element at the same height. Po-pla must therefore switch to its alternative form with a shorter height to make room.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Neue DIN Thai
As in the Latin alphabet (h, n), the Thai alphabet also has similarly constructed glyphs; if the ascender of Po-pla is shortened too much, it can be confused with Bo-baimai.
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Neue DIN Thai
Design experiment: The battle for the open space above the narrow Neue DIN Thai consonants

This is different from patterns like เตาปูปั้น or เตานี้ปึก (see image above), where a tone mark above Po-pla sits close to another tall stroke or mark at the same height, forcing Po-pla to switch to its short-ascender alternate to make room. While in เป็น (in the middle), that crowding never arises, so Po-pla keeps its default, full-height form.

A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Neue DIN Thai
Here, the relationship between Po-pla (ป) and the long vowel sign Sara-Ii ( ี Unicode: U+0E35) across all Neue DIN Condensed styles
A Script without Borders – An essay about Thai type design by Boom Promphan Suksumek – Neue DIN Thai
How tone marks work in the Neue DIN Thai variable font
Similarity between Neue DIN Latin and Thai: behavior of terminals and strokes across various stroke weights and widths.
Neue DIN Thai shown all weights and widths

Thai has its roots in a flexible, playful writing culture. In the digital age, there is still much to learn and discover: How can the fluid quality of hand-drawn letters, along with their playfulness, be revived in the context of the OpenType era?

Every writing system bears the traces of what its earlier tools made possible. Neue DIN Thai is an attempt to restore some of the Thai script’s flexibility. But there is still much to discover. Additional features and alternative characters are waiting to be explored, and every new width and stroke weight raises its own questions.

XXCondensed represents just one end of the family, from there, the journey leads all the way to XXWide, through all stroke weights and widths, through Italic and Retalic (that is, the left-leaning cursive). Go and have a play and see what you can discover! Download the entire family free of charge as a trial font.

Try Neue DIN Thai for free

Market Overview: Contemporary Thai Fonts from Various Suppliers

Looped plus Loopless

Looped

Loopless

References

Agenda in the images set in Pangea Mono (yet to be released) by Christoph Koeberlin.

The text was proofread by Lucy Beckley and translated into German by Jürgen Siebert. AI tools were used to a limited extent in the process.

  • [^1]: Michel Ferlus, “Origin of the Graph /b/ in the Thai Script,” in Southeast Asian Linguistic Studies in Honor of Vichin Panupong, ed. Arthur S. Abramson (Bangkok: Chulalongkorn University Press, 1997), 79–82. [PDF]
  • [^2]: Sommai Premchit, “Ramkhamhaeng or Ramkamhaeng?,” Journal of the Siam Society 76 (1988); the text addresses the transliteration and spelling of the name of the Sukhothai King Ramkhamhaeng, as well as a variant that omits the initial ”h”. [PDF]
  • [^3]: Anthony Diller, “Thai and Lao Writing,” in The World’s Writing Systems, ed. Peter T. Daniels and William Bright (New York: Oxford University Press, 1996); Nantana Danvivathana, The Thai Writing System (Hamburg: Helmut Buske, 1984). 
  • [^4]: Héctor Mangas, “The Contemporary Effects of Loops: Studying the Implications of This Unique Feature of the Thai Script,” Typotheque, 15 February 2025.
  • [^5]: Fontwerk, “Pangea,” 20 July 2020.
  • [^6]: Dome Sukwong and Sawat Suwannapak, A Century of Thai Cinema (London: Thames & Hudson, 2001)