By a hobbyist, for hobbyists
I wasted months printing proxies that towered over my Warhammer squad or looked like children next to my terrain. So I bought digital calipers, printed test cubes at every scale, and built this calculator to save you the same headache. Everything is tested on my Bambu Lab A1 Mini before it goes live.
I use these exact percentages in my own slicer. No guesswork. No file uploads.
I add a slight bump when my PLA or PETG shrinks while cooling.
My conversion logic assumes a 175 human baseline. Eye Level measures to 160cm. Top of Head accounts for hair and helmets at 175cm.
Tip: I always use Uniform Scaling (lock X, Y, and Z axes) in my slicer to avoid distorted models.
Pick the scales
I check what scale the sculptor modeled in — usually listed on Patreon or MyMiniFactory — then pick the scale my army actually uses. For my Warhammer proxies, that's almost always 32mm heroic.
Copy the exact percentage
I once eyeballed 115% for a 28mm→32mm conversion and my Space Marine looked like a bobblehead. The calculator gives me 114.3% — the number I verified with calipers on actual prints.
Paste and lock axes
I enter the percentage into Lychee or Chitubox, lock X, Y, and Z to uniform scaling, and hit slice. With PETG I bump the shrinkage compensation up by 1.5% because it contracts a bit more than PLA while cooling.
Before I commit a miniature to a long print, I check the scale first. A few seconds now saves me a lot of frustration later. These are the percentages I use myself, but if one of your prints comes out looking wrong, let me know.
Warhammer 40K and D&D heroic scale
Military kits to heroic gaming scale
Aircraft and vehicle models to true 28mm
WWII wargaming to true 28mm
Gaming minis to display painting scale
True scale to Star Wars Legion
Straight answers from my own experience at the painting desk.
Most people in the hobby treat Games Workshop miniatures as 32mm heroic scale, measured from eye level at roughly 160cm. To convert from true 28mm, scale your STL to 114.3% in your slicer. Your mileage may vary depending on the sculpt.
Multiply your 28mm STL file by 114.3% to get what most players call heroic 32mm scale. This accounts for the 175cm human baseline and eye-level measurement I use on STLACCESS. If your group uses something different, adjust accordingly.
PLA and PETG shrink about 0.2-0.5% during cooling. This is small enough that I do not add compensation. If you want maximum accuracy, print a test piece first and measure with calipers.
28mm true scale measures a 175cm human from eye level. 32mm heroic scale uses the same baseline but adds exaggerated proportions for detail and durability. A 32mm miniature ends up roughly 14% taller than its 28mm equivalent.
Games Workshop uses 32mm heroic for Warhammer 40k. A lot of D&D and Pathfinder miniatures are closer to 28mm true scale, though it varies by manufacturer.
Import the STL into your slicer (Chitubox, Lychee, PrusaSlicer, or Cura). Select the model, open the scale tool, and enter the percentage from the STL scale calculator. Lock the X, Y, and Z axes to uniform scaling. Apply the change and slice as normal.
1:56 is a ratio scale common in historical wargaming, including Bolt Action. It works out to roughly 28mm true scale when you use a 175cm human baseline. To convert 1:56 STLs to 32mm heroic, most people scale them to 114.3%.
Last updated: August 10, 2026
I started 3D printing back in 2017 with a cheap entry-level FDM printer. Like a lot of people back then, I spent more time troubleshooting bed leveling and failed prints than actually printing models for the table. In 2019, I tried turning the hobby into a business by running a commercial print service in Enschede, Netherlands. It didn't take long to realize that running a commercial print service completely drained the fun out of the hobby. The margins were tight, managing print queues felt like a grind, and I had no time left to print or paint minis for myself. Eventually, I shut it down and stepped away.
When I returned to 3D printing, I kept it strictly about the hobby. Now I print on a Bambu Lab A1 Mini — mostly PLA and PETG — focusing on Warhammer proxies, tabletop terrain, board game upgrades, and the occasional practical print. Zero commercial pressure, just enjoying the process.
The one thing that never stopped frustrating me? Scale. I would download an incredible proxy STL, slice it, print for 8 hours, and discover my new character towered over my Warhammer squad or looked like a child standing next to my terrain. I threw away enough mis-scaled models that I finally broke out my digital calipers and started working out the actual math.
Every percentage in this calculator is tested on my own printer. If a converted proxy comes off the build plate looking out of proportion with the rest of the unit, I tweak the calculations before publishing. I don't sell STL files, spools of filament, or printers. There are no paywalls or affiliate tricks. I built this for my own workflow and published it so other tabletop printers can save time and filament.
Plus, this calculator runs entirely in your browser. I never see your files.