Thai font · OFL

IBM Plex Sans Thai

ไอบีเอ็ม เพล็กซ์ แซนส์ ไทย

By Narongsak Chaiwong

Typography & Licensing Specialist, ThaiGraph · April 16, 2026 · Updated September 8, 2026

Information verified as of September 2026

อ่านหน้า ฟอนต์ IBM Plex Sans Thai เป็นภาษาไทย — พร้อมลิงก์ดาวน์โหลดและวิธีติดตั้ง →

<link href="https://fonts.googleapis.com/css2?family=IBM+Plex+Sans+Thai:wght@400;700&display=swap" rel="stylesheet">

@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans+Thai:wght@400;700&display=swap');

font-family: 'IBM Plex Sans Thai', sans-serif;

What IBM Plex Sans Thai is

IBM Plex Sans Thai (often shortened to IBM Plex Thai) is the loopless Thai extension of IBM’s global Plex type system, credited to Mike Abbink and Bold Monday in the Google Fonts metadata, with the Thai extension drawn by Mark Frömberg with Ben Mitchell per Frömberg’s project page. It is released under the SIL Open Font License in seven upright weights from Thin to Bold, with no italics, and has a looped companion, IBM Plex Sans Thai Looped. The official family name on Google Fonts and in the IBM/plex repository is “IBM Plex Sans Thai”, per the metadata and the plex-sans-thai package; “IBM Plex Thai” is the common short form. Note that Frömberg’s page documents the Looped cut; the credit for the loopless family follows the Google Fonts metadata.

The original IBM Plex was designed by Mike Abbink and Bold Monday in 2017 as IBM’s new corporate typeface, replacing Helvetica after 50+ years of use. The Thai extension was drawn in 2018 by Mark Frömberg with Ben Mitchell (per Frömberg’s page on the Looped cut) and reached Google Fonts on 18 June 2021 per the metadata, translating Plex’s humanist-with-engineering character into Thai consonant and vowel forms.

The result is the most technically rigorous free Thai corporate sans-serif currently available. Because it carries IBM’s backing, the spacing, hinting, and opentype features are production-grade from day one.

Character design and tone

IBM Plex Sans Thai uses sharp geometric terminals, a high x-height, and engineering-flavoured straight stems that echo the Latin Plex’s “humanist sans meeting machined hardware” brief. The loopless cut removes the traditional circle on consonants like ก and ถ in favour of clean open hooks.

What makes Plex Thai distinctive is the subtle flare at terminals — the end of a stroke on น or ม picks up a small optical widening that echoes Plex Latin’s slab-adjacent endings. Tone marks sit higher than on Sarabun, which suits the tall, architectural feel. The Looped cut is the same skeleton with traditional loops restored for legibility-critical contexts.

The Latin companion is of course IBM Plex Sans itself, which means the two scripts are drawn as one system. Cap heights, x-heights, and stem weights align precisely. A Thai sentence set next to an English sentence looks like one typeface, not two.

Weights and availability

IBM Plex Sans Thai and IBM Plex Sans Thai Looped each ship in seven upright weights from Thin (100) to Bold (700) with no Thai italics, per the Google Fonts metadata; italics exist only on the Latin IBM Plex Sans side. Download from Google Fonts or the IBM Plex GitHub repository.

The full Plex family also includes Plex Serif, Plex Mono and Plex Sans across multiple scripts, so a Thai + English + code-block design system can be built entirely from one family. File sizes for Plex Sans Thai are roughly 40-55KB per weight in WOFF2.

Loopless IBM Plex Sans Thai versus IBM Plex Sans Thai Looped

IBM Plex Sans Thai is the main, loopless cut for UI, headings and anything where Thai and Plex Latin must read as one system; IBM Plex Sans Thai Looped is the looped cut for long body copy and readers who expect the traditional head loops. They are two separate families on Google Fonts, added the same day (18 June 2021), with the same seven weights and the same OFL licence. Both metadata files (loopless, Looped) list seven upright static files and no variable axes.

The “loop” is the small circle at the stroke start of consonants such as ก ถ ภ ม. The loopless cut opens it into a hook; Looped keeps it. Everything else is shared, so the two can be swapped within one layout without line-height changes. Rule of thumb: dashboards, apps and headings use this page’s font; reports, manuals and long emails use Looped. For a single variable file in the same tonal family, Anuphan is a loopless Thai drawn from Plex’s Latin. See the loopless category for alternatives.

How to download and install IBM Plex Sans Thai

Download free from the Google Fonts specimen (“Get font” then “Download all”, seven static .ttf files, no sign-up) or from the Releases page of IBM’s own IBM/plex repository, which also publishes the family as the npm package @ibm/plex-sans-thai with subsetted .woff2 files and ready CSS. There is no variable file for this family; MDN describes this static model as one file per style, so pick two or three weights for the web.

• Windows / macOS — right-click the .ttf and Install, or double-click and Install in Font Book; the Thai side has no italics, so the Italic button in Word produces a synthetic slant
• PowerPoint hand-offs — File → Options → Save → Embed fonts in the file, per Microsoft; the OFL FAQ permits embedding (1.12)
• Google Docs, Canva, Figma — Figma includes Google fonts by default; Google Docs adds it through More fonts, which Google documents as available for Thai; in Canva filter by language or upload the TTFs on a paid plan. Type the full name with “Sans” — searching “IBM Plex Thai” finds nothing

Thai-speaking readers will find the full guide, including Word’s Complex scripts setting, on the Thai-language page.

Best use cases

IBM Plex Sans Thai is purpose-built for bilingual corporate identity, technical documentation and product UI. Strong briefs:

• Thai B2B and enterprise SaaS, particularly fintech, cloud, and dev tooling
• Technical documentation, API reference sites, engineering blogs in Thai
• Corporate annual reports and investor relations materials
• Bilingual product marketing for brands that use Plex as their global face
• Design systems for Thai government digital services that want a modern corporate feel

Where it doesn’t fit: consumer lifestyle brands (Plex reads as technical), long-form Thai editorial (the Looped cut is better, but serifs like Pridi still edge it), and traditional cultural contexts.

Pairings

IBM Plex Sans Thai pairs obviously with the rest of the Plex family, but also with other engineered sans-serifs. Three pairings:

• IBM Plex Sans — the canonical bilingual pairing, perfectly matched by design
• IBM Plex Mono — for code samples and tabular data inside technical Thai content
• Inter — when Plex feels too branded, Inter’s humanist skeleton reads as a neutral sibling
• IBM Plex Sans Thai Looped — the looped cut of the same family, for long body copy under loopless headings
• Anuphan — an independent loopless Thai drawn from Plex’s Latin, shipped as a single variable file
• Sarabun — neutral looped Thai body text when the whole system need not be Plex

See the typography learning hub for bilingual system guidance.

Licensing

IBM Plex Sans Thai is released under the SIL Open Font License, which allows free commercial use, modification and bundling. This is unusual for a typeface commissioned as a corporate identity — IBM open-sourced Plex specifically so the broader community could use it. Verify the licence at github.com/IBM/plex or on the Google Fonts specimen.

Frequently asked questions about IBM Plex Sans Thai

The questions people searching for IBM Plex Sans Thai ask most are whether “IBM Plex Thai” is the same font, whether it has italics or a variable file, and whether commercial use is allowed; the short, sourced answers are below.

Are IBM Plex Thai and IBM Plex Sans Thai the same font?

Yes. “IBM Plex Sans Thai” is the official family name on Google Fonts and in IBM’s repository; “IBM Plex Thai” is a common short form. Use the full name when searching font menus.

Does IBM Plex Sans Thai have italics or a variable font?

Neither, on Google Fonts. The metadata lists seven upright static files. For a variable Plex-toned Thai use Anuphan; for true Thai italics use Kanit.

Can I use IBM Plex Sans Thai commercially?

Yes. Both the IBM/plex repository and Google Fonts state OFL-1.1, and the OFL FAQ allows any design work including logos (1.1) without required attribution; the only restriction is selling the font files by themselves (1.5–1.6). See the Thai font licensing guide.

Information verified as of September 2026