I kill a lot of typefaces. It’s not that I don’t like them — quite the opposite. I think they deserve better. I love type too much to look at a half-baked idea and call it close enough, and yet sometimes a design’s full potential is simply out of reach. I resurrect typefaces, occasionally, when I find I’ve grown tall enough to try again.
Any designer must eventually reckon with this feeling. There’s no faster path to burnout than the stubborn refusal to admit defeat: you learn to recognise quality much sooner than you can achieve it. So you learn to pick your battles, to put some projects back in the drawer and come back later.
This is why I’m generally hesitant to show a design before it’s done. It’s not for fear of someone else copying the idea, but out of a reluctance to let people down when a concept they become attached to ends up as one of the many that never makes it.
In early 2021, I released MD IO as a work-in-progress typeface via Future Fonts. I’d started drawing it a few months earlier, and I was confident both that finishing the design would be feasible, and that feedback from real-world users would be key to its success.
The brief for IO was simple: legibility above all else. Rather than readability, which refers to how comfortable a typeface is to read overall, legibility refers to how easily a single character can be identified in isolation. Does the 6 look like an 8 when you’re not wearing your glasses? Is that a zero or a capital O?
1 from the lowercase l (which has no upper-right serif) and capital I (which does).
8 is visibly narrower at the top to distinguish it from the capital B, while the 6 uses a geometric construction for even greater distinction.
0, either dotted or slashed, to avoid confusion with the cap O.
There are many reasons to release a typeface on Future Fonts, and to be transparent, in 2021 the ability to begin selling IO before needing to finish the whole typeface was a major one. Even more valuable in the long term though was the feedback I got from real-world users: which glyphs are working, and which still need work. Some of the original letterforms were unambiguous, but not intuitive. Others were obvious up close, but in smaller sizes could be misread.
For close to three years, developing IO was a process of continual iteration and improvement, with many different people (myself included) testing the design and documenting any potential issues. And all the while, behind the scenes, that same feedback was helping to inform another, much more ambitious project.
MD UI has danced at the edge of my abilities ever since it was conceived, on the same afternoon I began drawing MD IO, in the autumn of 2020. To tell the truth, I did not release it on Future Fonts (or even talk about it publicly), because I didn’t know if I could pull it off. It’s the most complex project I’ve ever worked on by a wide margin. Over the past five years, there have been many times when I considered letting it go, dropping it in the archive and taking it off the to-do list.
And yet I didn’t. As MD IO became more popular, and as it developed into a sizeable type family in its own right, UI grew with it. Together with Luke Charsley, we’ve taken the lessons of IO, along with the experience from countless other designs we’ve worked on, and quietly distilled them into something I’m truly proud of. Let me, finally, tell you about it.
When we think about reading, we tend to picture books, or magazines, or business reports. Blocks of text, traversed from beginning to end. There’s another kind of reading, though, one which I think we do much more often without really noticing it.
It’s a kind of instantaneous scanning of a word or two at a time: the hour on a smartwatch, or the label on microwave dial, or the URL in your web browser. I like to call this interfacing, because it’s less about digesting information (or experiencing the text) than about interacting with your immediate surroundings. You don’t think of it as reading at all — it just happens.
MD UI is a typeface for interfacing. It’s a design optimised from the ground up for word- and sentence-level performance, with an appearance that doesn’t try to be neutral, but doesn’t surprise or distract the reader either. It’s a typeface meant to be read without being noticed.
Helvetica was first publicly shown in June of 1957, which makes it about four months older than Sputnik, the first artificial satellite. 12 Angry Men was still playing in theatres, and in a few short weeks, John Lennon and Paul McCartney would meet for the first time. Satellites, Hollywood and the music business have transformed profoundly in the seven decades since that time. But we still use a lot of Helvetica.
Indeed, a huge amount of the text we see in everyday life follows almost directly in its footsteps: the same grotesque or neo-grotesque model, the same emphasis on regularity and geometric precision. As Zuzana Licko succinctly put it, we read best what we read most — and why wouldn’t we keep using what we read best? Upon consideration, it’s no great surprise that typographic culture moves so glacially.
There’s a tension here, though, which has intrigued me for a long time. On first principles, neo-grotesque typefaces are not optimal for interfacing: their closed apertures can blur together and reduce legibility; their overly-similar shapes are easily confused for one another. And yet they’re what we keep using. What they lose in fundamental clarity, they make up for in familiarity — they follow the principle of least surprise. But can we do better?
MD UI is a neo-grotesque tuned for maximum performance. It takes the basic model we’ve come to expect, and through a number of carefully-balanced modifications, addresses as many of its typical limitations as possible.
The typeface comes in three size-specific families: XS, XL, and a standard cut for most usage in between. Rather than absolute point size, these refer to optical size, or the apparent size of text relative to your overall field of vision. Text that’s physically small but read from a close distance can have the same optical size as text that’s physically large but seen from far away.
At small optical sizes, MD UI’s apertures widen, and robust ink traps push light into the areas where strokes meet, keeping the silhouettes of glyphs distinct. Diacritics and punctuation get larger. Less common glyphs, like numbers, use more legible geometric or humanist constructions, adapted to blend in with the rest of the character set. And overall, a slightly squarer, higher-tension curve language keeps internal spaces open and visible, while aligning just a little better with pixel grids in digital environments. In print, we tested this typeface down to 4pt.
t become proportionally wider, and ink traps prevent stroke intersections from clogging with ink or becoming muddy.At large sizes, the ink traps disappear, the width narrows a little, and UI’s spacing and apertures tighten to embrace the precision and regularity of the genre. Here, the higher curve tension allows round glyphs like o and e to take up more space on the page, increasing the typeface’s impact and reinforcing the uniformity of the shapes.
MD UI VF wraps all 48 static styles into a single variable font, with a continuous interpolation space allowing you to fine-tune everything from the weight (from Thin to Ultra-bold), optical size (XS to XL), and even the italic angle (upright to 12°). In modern web browsers, the size-specific adjustments will be set automatically by default for text between 6 and 48pt.
As the names suggest, MD UI and MD IO are designed as a pair. Their vertical proportions match, and their visual language is intended to substantially overlap. By nature of their differing concepts — IO emphasising single-glyph legibility, UI word- and sentence-level readability — they diverge in a few places, however the similarities allowed each to influence the other during development.
Since the end of 2020, I’ve been using MD IO in just about every situation that calls for a monospaced typeface: writing code, drafting blog posts, spreadsheets. Since early 2023, I’ve been testing MD UI in much the same way: websites (using a browser extension to change the default font), Slack, my email client. I run Linux on my home PC, and various development builds of UI have served as my system font there as well.
All the while, I’ve been keeping notes, making small changes to fine-tune the shape of a line or the width of a space. I developed some custom tools to help proof different combinations of weight and optical size, but also enforced weeks-long breaks from looking at the typeface, since coming back with fresh eyes often helps spot problems which are easy to miss from up close.
This did not make for a quick development process. In August 2024, we realised that the smaller optical size was too narrow — widening it (by about 6%) involved altering over 400 glyphs. Testing that change alone took weeks. But while developing UI might have taken five years, I still think it’s worth it.
I grew up in the twilight of the International Typographic Style. The expressive, experimental, David Carson grunge of the 90s and early 2000s was on my radar but peaked before my time: it was the norm to push back against, no longer the fresh new thing. Just as it had been a generation before, the Swiss style was the glass of cold water in the desert.
While I learned more over the years about the history of design, and many of my views changed as I understood the context of the visual culture around me, the reverence I had for those mid-century neo-grotesques never went away. Drawing MD UI, it wasn’t just the scale of the project that intimidated me, it was the feeling that I needed to add something to a conversation so much larger and older than myself.
I didn’t want to make yet another imitation of the classics. I wanted to make something better. That’s a little bit of hubris, sure, but the Swiss style didn’t become so ubiquitous because it wins on qualitative analysis. Helvetica isn’t perfect, it’s just familiar.
MD UI isn’t so much a revival of the International Style as an anticipation of its potential future. It’s an attempt to take the familiar and push it just one step further; to fix a couple of the annoyances while leaving what works alone. That’s easier said than done. But it’s done.
Since 2024, every typeface we release now supports the Latin M character set, which covers Vietnamese and Pinyin, along with over 400 more languages. MD UI is no different, and today we’ve also updated MD IO to match the same standard.
All styles of MD UI also include a handful of OpenType features to enable you to fine-tune the typeface’s appearance and behaviour. By default, the dots of letters like i and j, along with punctuation and diacritics, are circular, giving the design a more contemporary, approachable character; a set of alternate square dots draws on the mid-century roots of the genre, giving a stronger sense of maturity and confidence.
The Latin writing system is a complex dance of rhythmic vertical lines, and keeping this rhythm consistent plays a major role in readability. For that reason, both the capital I and lowercase l are rendered as single strokes by default, since their similarity is rarely a problem in the context of a word. Where the distinction really matters, however, an alternate set of ‘legible forms’ makes the glyphs unambiguous — and, in similar contexts, a ‘slashed’ variant can help differentiate the zero from the capital O.
More than any other, this typeface is one I think should speak for itself. We haven’t put together a big marketing campaign or a dedicated microsite to showcase it in hypothetical use cases — we’ve rebranded the foundry with it. Since May last year, we’ve been working on a refresh of our visual identity with MD UI at its core, and using that project as one more opportunity to test the typeface in the real world.
If you’re interested in doing the same, you can download a trial version of the complete UI family to test in-situ. We don’t subset our trial fonts, so you can access the full range of glyphs, weights, and OpenType features.
A complete list of features and details is available in the PDF specimen for MD UI. Licensing starts at €50 for Commercial usage, with variable fonts available (on request) with licenses for the full typeface family.
Years ago, I watched an interview which has stuck with me ever since: the designer of some new supercar was being asked about its price, a cool two million euros. The interviewer asks, “If it could cost three million euros, what would you change?”, and the designer replies, “Nothing. This is the best car we can make.”
If we had another five years, would MD UI look different? There are plenty of things I might add — with 160,000 characters in Unicode, language support is never complete. And yet, even with another decade to work on it, I wouldn’t want to change the fundamentals at all.
This is the best car we can make.