How small can you
3D print text?
With a 0.4 mm nozzle, bold text lying flat stays readable down to about 5 mm letter height and regular text to about 8 mm. The rule behind it: every stroke should be at least twice the nozzle width, so 0.8 mm. Text on a vertical wall can go a little smaller, down to about 4 mm.
By Philipp Baldauf · Updated September 29, 2026
The rule of thumb: stroke width at least 2x the nozzle
Letter height is what people ask about, but the stroke width is what fails. A slicer builds each stroke from walls, and one wall is about as wide as the nozzle (0.42 mm for a 0.4 mm nozzle). Two walls side by side make a solid, stiff stroke. So the minimum is stroke width of 2x the nozzle diameter: 0.4 mm with a 0.2 mm nozzle, 0.8 mm with a 0.4 mm nozzle, 1.2 mm with a 0.6 mm nozzle.
To turn that into a letter height, you need the font's stroke ratio. A heavy font like Anton has strokes around 20% of the capital height. A regular sans like Roboto or Poppins sits at 12 to 13%. Thin scripts can drop to 5% or less. Divide 0.8 mm by that ratio and you have the smallest capital height that prints solid: about 4 to 5 mm for Anton, 6 to 8 mm for Poppins, 16 mm or more for a 5% script. Our font guide lists the ratio for all 18 fonts in the generator.
Minimum letter height by nozzle
Capital letter height for readable, solid letters. Flat means the text lies on the bed and faces up. Vertical means raised text on a side wall, with the letter height running up the Z axis.
| Nozzle | Line width | Min. stroke | Flat, bold font | Flat, regular font | Vertical text | Layer height |
|---|---|---|---|---|---|---|
| 0.2 mm | 0.22 mm | 0.4 mm | 2.5 to 3 mm | 4 mm | 2 mm | 0.06 to 0.1 mm |
| 0.4 mm | 0.42 mm | 0.8 mm | 5 to 6 mm | 8 mm | 3.5 to 4 mm | 0.12 mm |
| 0.6 mm | 0.62 mm | 1.2 mm | 8 mm | 12 mm | 6 mm | 0.2 mm |
Typical values from nozzle geometry and common slicer defaults, for PLA. Script fonts need more, see the font table. These are minimums for readable letters, not for pretty ones: add 50% if the text is the main feature of the print.
Why vertical text can go smaller
Lying flat, every part of a letter is drawn in X and Y, so it is limited by the line width. On a vertical wall, horizontal strokes (the bars of an E, the top of a T) are built from stacked layers instead. At 0.12 mm layers, a 0.5 mm horizontal stroke is four layers tall and comes out crisp. Only the vertical strokes still depend on the line width.
That is why the lettering on the side of a printed box often looks sharper than the same text on its lid. The trade-off: vertical text needs a part with a real side wall, and it shows layer lines across the letters. For names, keychains and signs, flat text is the normal choice. The 3D print text guide covers orientation in more detail.
How high to raise the letters
Raised text on a plate needs enough height to read and to take a colour change, but tall thin letters wobble and snap. Keep the raised height at about 1 to 2 times the stroke width.
| Raised height | Layers at 0.2 mm | Good for | Watch out |
|---|---|---|---|
| 0.4 mm | 2 | Colour contrast only, flush-looking text | Barely felt, hard to paint |
| 0.6 to 1 mm | 3 to 5 | Keychains, name tags, desk plates | The standard. Works with a filament change. |
| 1.5 to 2 mm | 8 to 10 | Kids' bag tags, tactile labels, signs read from the side | Needs strokes of 1 mm or more |
| 3 mm and up | 15+ | Large signs and letters with 2 mm+ strokes | Thin fonts snap; strings between letters |
In NameSTL, the Thickness slider (0.5 to 10 mm) sets the letter height. With the outline, keychain and pet tag bases, the plate is 2 mm thick and reaches 0.5 mm up into the letters so both fuse, so the letters stand about Thickness minus 0.5 mm above the plate.
0.12 mm vs 0.2 mm layers for text
Layer height changes less than most people expect. It does not make strokes thinner in X and Y, only finer in Z.
Use 0.2 mm when
The text lies flat and the letters are 8 mm or taller. Raised text at 0.2 mm has clean vertical sides, and a keychain takes about 25 minutes on a Bambu A1 mini instead of 40.
Use 0.12 mm when
The text is vertical, very small, or rounded on top. Also when you raise letters only 0.4 to 0.6 mm: at 0.12 mm you get four or five layers instead of two or three, so the colour change is cleaner.
Variable layer height
Bambu Studio, OrcaSlicer and PrusaSlicer can print the plate at 0.2 mm and the letters at 0.12 mm. It saves time on big signs where most of the height is the plate.
Arachne walls: the setting that saves thin text
Classic wall generators use a fixed line width. A 0.6 mm stroke is too narrow for two 0.42 mm walls and too wide for one, so the slicer leaves a gap, fills it with a messy gap fill, or drops the stroke. Arachne varies the line width along the stroke, so that same 0.6 mm stroke becomes one clean line of 0.6 mm or two of 0.3 mm.
Cura 5 and PrusaSlicer 2.5 and newer use Arachne by default. In Bambu Studio and OrcaSlicer it sits under Quality, Wall generator. Two related settings decide what gets dropped. Minimum feature size (default 25% of the nozzle, so 0.1 mm) removes anything thinner. Minimum wall width (about 85% of the nozzle) sets the thinnest line it will lay down. Lowering them lets hairlines appear, but those lines are fragile and can smear.
Arachne cannot make plastic thinner than the nozzle can draw. It stretches the limit by maybe 25%, it does not remove it. If a stroke is under half the nozzle width, scale the text or change the font.
Check your text before you print
The slicer preview tells you everything in two minutes. Do this for any text under 10 mm.
- 1
Slice and open the preview
Switch the preview to line type or feature view so walls, infill and gap fill show in different colours.
- 2
Scrub to the top layers of the letters
Every stroke should have at least two wall lines. Strokes drawn as one thin line are weak. Missing strokes mean the text is below the minimum feature size.
- 3
Look at the counters
The holes in e, a and o should still be open. If they are filled, scale up or use a wider font.
- 4
Check the dots and accents
Dots on i, j and umlauts are tiny islands. If they are thinner than 1 mm across, they may not stick. A plate under the text holds them.
- 5
Scale in the slicer, not in your head
Use the scale tool to set the exact size you want and read the dimensions. Then check the preview again: scaling down by 20% can push a font past its limit.
How big should text be to read from a distance?
Sign makers use a rule of about 25 mm of letter height per 3 m of reading distance for comfortable reading. The minimums above are for text held in the hand.
| Reading distance | Capital height | Example |
|---|---|---|
| In the hand (30 cm) | 5 to 8 mm | Keychain, tool label, pet tag |
| On a desk (1 m) | 10 to 15 mm | Desk name plate, place card |
| Across a room (3 m) | 25 mm | Door sign, classroom label |
| Down a hallway (10 m) | 80 mm | House name, workshop sign |
What NameSTL does for small text, and what it can't
The generator builds watertight letters and merges cursive joins, so a script name doesn't fall apart. With a plate behind the letters, dots and accents stay attached. You set the final size by scaling in your slicer.
It can't make a thin font thick. There is no stroke weight slider, so if your font is too thin for the size you want, pick a heavier font or print bigger. For text under 5 mm, a 0.2 mm nozzle is the real fix. Why 3D printed letters break covers the other failure modes.
Questions people ask
What is the minimum text size for 3D printing?
With a 0.4 mm nozzle, about 5 mm capital height for a bold font and 8 mm for a regular one, printed flat. Text on a vertical wall can go down to about 4 mm. A 0.2 mm nozzle roughly halves these numbers.
How thin can a letter stroke be?
Aim for twice the nozzle diameter: 0.8 mm with a 0.4 mm nozzle. Arachne walls can print strokes down to about one nozzle width as a single line, but they are weak. Anything under about 0.1 mm is dropped by the slicer.
How do I 3D print small text?
Use a bold sans font, print it flat or on a vertical wall, and switch on Arachne walls. Drop to 0.12 mm layers, slow the first layer, and check the slicer preview for missing strokes. Under 5 mm letter height, change to a 0.2 mm nozzle.
How tall should raised text be on a 3D print?
0.6 to 1 mm above the surface is standard for keychains and plates. That is three to five layers at 0.2 mm, enough to feel and to switch colour. Go to 1.5 or 2 mm only if the strokes are at least 1 mm wide.
Does a smaller layer height help with small text?
Only in Z. Layer height makes vertical text, rounded tops and colour changes cleaner, but a stroke drawn flat on the bed is still limited by the nozzle width. For thinner strokes, you need a smaller nozzle.
Why is my thin text missing in the slicer?
The stroke is below the slicer's minimum feature size or too narrow for one wall. Switch to Arachne, scale the text up, or use a heavier font. Lowering the minimum feature size shows the hairline, but it will be fragile.