Variable Fonts: An Introduction

Carl Shank • December 9, 2025

Variable Fonts: An Introduction

History & Use

“Variable fonts are a single font file that behaves like multiple fonts.” (John Hudson) The technology behind variable fonts has been around for a while. Starting in the 1990s, interpolation and extrapolation have been used to create different masters, and weights in typefaces. For example, by designing a regular and bold weight a semibold could be interpolated from the two masters. 



Apple Computer, in its development of the Macintosh computer in the early 80’s, also introduced the Apple LaserWriter™ and the LaserWriter Plus. Using a new technology

called “Postscript,” licensed from Adobe Systems, a built-in font description language in the Laser-Writer’s ROM (read-only memory) converted screen fonts on the computer screen, through a mathematical process, to 300 dpi (dots-per-inch) output. (Exciting at the time!)


Users wanted, and soon got, true WYSIWYG (pronounced wizzywig— what-you-see-is-what-you get) operating environments. With the advent of Adobe’s ATM (Adobe

Type Manager™), and Apple’s TrueType fonts, the on screen font “jaggies” were replaced by the outline representation of the font, so that the screen faithfully represented the final printed output. Fonts could be “downloaded” per job to the Postscript printer, even if the printer did not have the specified fonts inherent in its ROM files. 

QuickDraw

“QuickDraw” gave the added advantage of producing laser-like output even from a nonPostscript printer. With QuickDraw, the font outlines are processed by the computer and sent to the printer for output. Software packages now skew, bend, shrink, condense, expand, rotate and manipulate typeforms. Apple’s System 7.x and Windows 3.1x included several TrueType fonts that were installed with the system software.


Basic QuickDraw was designed for the earliest Mac models with their built-in black-and-white screens and was seen on systems such as the Macintosh Classic and Powerbook 100 computers. Color QuickDraw was introduced with the first Macintosh II systems, supporting up to 256 colors. 32-Bit Color QuickDraw was part of Mac System 7 and supported up to millions of colors.


QuickDrawGX added various curve-drawing commands and introduced TrueType as its basic font system. “The ability to do kerning, tracking, and justification, as well as ligatures and ornamental forms of various characters, is provided by the line layout routines, supported by the QuickDraw GX smart font format. The line layout routines work with the typographic information contained in the TrueType GX and Type 1 GX fonts to give you a ton of control over how text is placed on a page. Because QuickDraw GX typography is fully integrated with graphics, you can rotate, skew, and change the perspective of typographic shapes the same way you can geometric shapes. You can use the text shape to draw a line of text with one style. The glyph shape enables you to draw text in several styles and graphically manipulate each glyph.” (Getting Started With Quickdraw, Sep 1993)


When you click OK in a Print Dialogue box on your computer, the application for text specifies font, size, style and so forth. For graphic objects, the application specifies the shape, size, line weight, fill pattern, and other attributes. QuickDraw prepares a script of actions necessary to draw the whole page and is generic enough to work with any type of printer. For the LaserWriter, the driver translates the QuickDraw script into a Postscript program and sends that to the printer.


While many of its component features live on in the current Macintosh environment as OpenType Variable Fonts, GX itself was formally “killed” with the purchase of the NeXT system and the adoption of the Quartz imaging model in Mac OS X. GX proved too large, with its API (Application Programming Interface) demanding several books, and required speeds not available on the classic Mac 68000-based platforms, like the Mac Plus.


Multiple Masters Fonts

Multiple master fonts (or MM fonts) are an extension to Adobe Systems Type 1 PostScript fonts. Multiple master fonts contain two or more “masters,” that is, original font styles, and allow a user to interpolate between these masters along a range of continuous “axes.” Custom styles can then be generated from a single font file programmatically.


Most MM fonts support one or two (sometimes three) of the following variables — Weight (wt), Width (wd), Optical size (op) and sometimes Style. Width allows the character width to be extended or compressed. While other software allows for shrinking or widening type, the results from a multiple master font are superior. Vertical strokes in enlarging or reducing characters tend to be proportionally thicker or slimmer, giving an uneven appearance. MM fonts with a width axis are designed to scale appropriately.


Weight allows the character weight to be modified, typically from light or thin, through regular, to extra bold. Optical size allows the character shape to be modified based on how large it will appear to the reader. At small sizes, small details such as serifs and thin lines such as stems are typically bolder. The "x-height" (the height of a lower case "x") is also a larger proportion of the total font height, and the characters may be extended slightly. These changes are designed to make small type easier to read. 



Style, the least used of the multiple master axes, allows any other font property to be continuously modified. One such example is changing the serif style from wedge (triangular) to slab (rectangular).


This technology failed for at least two reasons. First, users were forced to generate “instances” for each font variation, littering their hard drives with font bearing names, like MinioMMIt_519 wt 539 wd 42 op. This code was for the Minion Italic font with a weight of 519, a width of 539 and an optical size of 42. 


The second reason for the MM discontinuance is that most font designers have generally preferred to release fonts in specific, individually fine-tuned weights and styles. Thus, the current Open Type Minion Pro font has 64 variations carefully crafted to suit most any typographic need and context.



Current application support for MM fonts is sparse. However, font design tools such as FontLab and FontForge can edit MM fonts, and can export them into other font formats as needed. Adobe Type Manager (ATM) is required for MM support on Windows and the "Classic" Mac OS (9 and below).


A technical note concerns a key question on which sizes to interpolate to. “In the Thesis typeface developed by Lucas de Groot (See BLOG Post Advances in Typography: Late Twentieth to Twenty-First Centuries A Historical Sketch (Part 3) December 1, 2025), de Groot's choice of weights to release was developed using an "interpolation theory". The optical interpolation b, in the three stems a (thinnest), b (interpolation) and c (thickest), is set to the geometric mean of a and c, i.e. b² = ac (as opposed to the linear arithmetic mean).” (Wikipedia) Popular MM Fonts — ITC Garamond MM, Minion MM, Myriad MM, Adobe Jenson MM.


Open Type Variable Fonts

Open Type Variable fonts build directly on the technology introduced to TrueType by Apple in the QuickDraw GX graphics environment. Of similar vintage, Adobe’s multiple master format approached similar concepts in a different way. How do we know that Variable Fonts don’t also have a declining future? The need for more compact dynamic webfonts is part of the answer. “Variable fonts also have the potential to enable new kinds of typography for electronic documents, responsive to things like device orientation or even viewing distance. Compact and faster fonts also provide significant advantages for embedding fonts in devices, especially for East Asian (CJK) and other fonts with very large glyph sets and character coverage. The smaller device and disc footprint of variable fonts has been a major factor in encouraging support for the technology in software companies.” (https://medium.com/variable-fonts)


An Open Type Variable font contains one or more axes that each provide particular variation between different extremes of a typeface design. The format also allows for the possibility of intermediate designs, for the whole glyph set or for individual glyphs, to provide finer control over the design as it changes across the variations design space.


Unlike MM fonts, an Open Type Variable font contains only a single set of glyph outlines “and the other extremes or intermediate shapes are defined as deltas from those outlines. So, for example, a font may contain a set of glyph outlines that correspond to the regular weight and width of a typeface, and the lighter, heavier, narrower, and extended designs will be expressed in the font data as movements of outline nodes relative to that outline.” (Medium.com) Any position within the design space can be a named instance. 

This is a sample of using a Variable Font in Adobe InDesign. Note the Width and Weight axes. (For Demo purposes only)

An Example. A client wants you to professionally typeset the following paragraph — "Aleka, the Norwegian dog, pal to Cinthia, is 2 3/9 years old. She has been adopted from a rescue center in Norway, badly treated, bruised and emotionally distraught. Cinthia nursed her back to life with the joys of being loved in her living. This dog travels everywhere with her owner." Her requirements are as follows — Use justified Minion type in a block 18 picas wide by 11 picas deep and in 14 point on automatic leading at 16.8 point. She wants you to use real fractions. The block must be easy to read and pleasing to the eye.


The draft below gives some options a professional typographer or printer might use. Notice in Example 1 all of the text required does not fit and the spacing between words is too extended. The fraction is okay using Minion Open Type Pro. Example 2 uses Minion Variable font. Note the darker type, thus easier to read, and the word spacing is pleasing to the eye. Example 3 goes back to Minion Pro but this time uses hyphenation. The problem is too many hyphens in this short block. Example 4 uses a Minion MM font with only one hyphen, but again the text is pleasing to the eye. Which one would you choose?

Two Variable Fonts highlighted in this piece are Roboto and Inter. A good place to see and experiment with variable fonts is AxisPraxis at https://www.axis-praxis.org/specimens/. Note the insert on the FFMeta Demo Variable Font.

 

Creating a Variable Open Font, using Glyph software, can be found at https://glyphsapp.com/learn/creating-a-variable-font


This is a sample Variable font, FF Meta Variable, noted in axis-praxis.org. Note the axes on the right of the paragraph.

Successful Layout & Design

By Carl Shank April 7, 2026
The King James Bible (KJV), commissioned by King James 1 in 1604 and published in 1611, has been a profound Bible translation and masterpiece of beauty through the ages. It has been one of the most influential English translations of the Bible. Its history combines politics, religion, and literary achievement in early modern England. It has an elevated, poetic style that influenced many later writers. It has been prized for its literary beauty, historical continuity and memorability in public reading and worship (ChatGPT).
By Carl Shank April 6, 2026
Responding to AI and Digital Babylon H. Carl Shank April 4, 2026 Austin Gravley, a former Social Media Manager of The Gospel Coalition, and now the Director of Youth Ministry at Redeemer Christian Church in Amarillo, TX, is writing a book on AI and the digital revolution taking place. He compares this Digital Babylon and its captivity and its exiles to Christians living under the overwhelming influence of an active anti-Christian developing AI. Piecing together his comments with those of many others on the advancing scene of AI on our lives, several themes come to mind. First, AI is not God. While there are some in the Silicon Valley who might wish or see AI as a unifying, ontological force that can shape or rule our lives — the Super Machine —others remind us that this is only technology. And as advanced as AI is and becomes, God is still sovereignly in control of it and our lives. Jason Thacker, professor of philosophy and ethics at Southern Seminary and Boyce College, writes — “We must engage these issues, rather than respond after their effects are widely felt. But we don’t have to face today or tomorrow with fear. God is sovereign and his Word is sufficient for every good work, so we are able to walk with confidence as we apply his Word to these challenges with wisdom and guided by his Spirit.” ( The Age of AI: Artificial Intelligence and the Future of Humanity , Zondervan, 2020) A recent storm that darkened my community and scuttled Internet services reminded me of that. Even AI data centers, growing to over 3,000 in 2025 nationwide, are not immune to power disruptions and total blackouts. AI pundits may claim to have control procedures to keep the Internet and AI running cannot promise it to be so. We need to keep this in mind in the Digital Babylon age, as was needed to be kept in mind by Israel in the Babylonian Empire age in biblical times. Babylon went through many iterations, but will be defeated by God at the end of the day, as noted in Revelation. Digital Babylon will experience the same demise. This is not prediction, just Bible truth. We as believers need to hold on to such truth. Second, AI is still technology. Indeed, advanced and advancing technology, but not human. Matthew Schultz in a recent mereorthodoxy.com article notes— “Technology has existed since the Garden and is an integral component of our cultural mandate. We should also remember that one of the core distinctions between the Creator and his creatures is that we never create matter but merely (!) rearrange it. This becomes clear whether we consider an ancient farmer in Mesopotamia irrigating a plot of soil, a medieval peasant in Northumbria weaving a basket from flax, or a young musician in London taking the raw outputs of machine sound, adjusting its pitch, volume, and length, and incorporating it into a DAW loop. While there are all sorts of important distinctions and qualifications between pre- and post-industrial craft, there is no metaphysical distance between the two.” ( Artificial Intelligence Is A Technology , Feb. 26, 2026). AI may be the harbinger of a new Industrial Age, but though changes will be major and sometimes severe, the human side of the equation cannot be discounted or counted out. Part of my retired status as a pastor and theologian is that of a typographer restoring old type faces and doing a deep dive into the history of type. Two historical typographical truths stand out. Although the Renaissance age brought movable type from Gutenberg and others into the machine age, the typographical flair of those ancient scribes with pen-drawn exquisite type remained a stylistic standard. The second note is that with the Industrial Age, while affecting the quantity and speed of type development and printing, master type craftsmen rebelled against machine driven type for more organic typefaces. This was seen, for instance, in the type movement spawned by William Morris (1834–1896). William Morris was an Arts & Crafts designer who founded the Kelmscott Press (1891), reviving hand craftsmanship in printing. His work influenced the twentieth century private press and type revival movements. Lettering became a vehicle for breaking convention. Led by figures such as Morris, there was a decided reaction against industrialization, seeing machine-made goods as dehumanizing and ugly. Handcraftmanship, honesty in materials and utility fused with beauty made up much of what was called the Arts & Crafts Movement. That movement was rooted in medieval guild ideals and morality in design. (For an expanded history of type development, see “Advances in Typography: A Historical Sketch — Three Parts” in the blogs by CARE Typography, www.caretypography.com , Nov. 8, 2025, Nov. 18, 2025 and Nov. 20, 2025) Third, AI affects everyone everywhere. Austin Gravely, a former Social Media Manager of The Gospel Coalition, raises and answers the query — “’So what?’, you may think. ‘I’m not an Internet technician. I’m not a fan of AI. I’m not planning to change how I use the Internet. Why does any of this matter to me?’ To put it bluntly: you are naive if you think these disruptions won’t directly affect you, or indirectly affect you through the effect they will have on others. If the iPhone, social media, and AI have taught us anything, it is that you are impacted by these events regardless of whether you participate in them or not.” ( The State of the Internet: 2026 , mereorthodoxy.com, March 30, 2026) He goes on to say — “A changing Internet will change you. It will change you in ways you can see and in ways you can’t. It will change those you live with, work with, play with, build with, and fight with. It will change what is possible, probable, permissible, and prohibited in your life, your vocation, your church, your neighborhood, and any other physical space the Internet touches.” I recall my 99 year old mother who passed away a couple of years ago in a nursing facility. She was one of those survivors of the Great Depression and World War Two who dismissed the first moon landing and had her flat screen TV removed from her room for fear the government was watching. She lasted for nine years in the same private room in a modern nursing center. She was attended by doctors and nurses and staff who used AI on their computers and other care devices. She even had a modern digital phone removed from her room and refused to learn it. While she personally rebelled against her AI driven machine age, she could not escape those who used such technology for her care. We cannot isolate ourselves from AI and its advancing development, no matter how isolated we try to be. Fourth, AI can be either a blessing or a curse. Again, Matthew Schultz notes — “Our task is not to develop a unique theology of AI but to catechize our members into a people who can wield this technology without becoming captive to its internal logic. Like alcohol, artificial intelligence will become a test of character, a dangerous good that divides the foolish from the wise.” He says “Yet the greatest danger is both more pervasive and less obvious: AI is much more likely to be deployed as a multiplicative layer that allows ever more efficient micro-targeting of digital services and physical products by industries that already profit from compulsive behavior. The advent of hyper-personalized, real-time engagement strategies will require legislative safeguards, especially if AI leads to video advertisements generated in real time for an exhaustively mapped individual profile.” We must seek to “humanize” AI and employ it “humanly.” We must resist the phenomenological bent toward unbelief in AI development and pressures. We must once again learn to think critically and pervasively and biblically about AI. Our young people must be taught prescriptive critical thinking practices, rather than unwittingly and ignorantly giving in to what their phones and computers spit out. Church and ministry pastors must pastor rather than let AI bots plan, prepare and even give their sermons. We must learn to smartly negotiate with the “Magnificent Seven”— Apple, Microsoft, Alphabet, Amazon, Meta, Nvidia and Tesla — rather than blindly following their lead. Convenience and speed must not be allowed to overtake and overcome careful, sustained and critical thinking and acting. “To give language to this change, we must take the best of Christian thinking regarding the social and political imaginary and apply it to the economic imaginary of life under the glowing shores of Digital Babylon, and that kind of work cannot be done with quick hot takes. It will take slow, deep, and thoughtful meditation to apply the riches of Christian thought to making sense of the companies that got us here and where they are taking us.” (Austin Gravley, The State of The Internet: 2026 ) I am both excited and wary of AI. I have learned to be much more cautious about social media and the videos and photos and information they give. Much of it has been and is being AI produced and tweaked. Spammers use AI technology to wrest thousands of dollars from unsuspecting senior citizens. Schools are requiring students to turn off their cell phones or “bag” them until after school hours because of the insidious nature of AI generated stuff. I value more and more of a face-to-face approach in teaching and learning and mentoring others. And we must adopt a state of “believing is seeing” rather than a non-Christian scientifically sanctioned “seeing is believing” approach to truth and justice.
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