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STL Scale Converter
Exact Slicer Percentages for Miniatures

Stop wasting filament and resin on mis-sized proxies. Tested with digital calipers on a Bambu Lab A1 Mini, this free tool calculates exact scale percentages for tabletop miniatures, terrain, and multi-part kits.

Runs instantly in your browser. Zero file uploads, zero installation, 100% offline-ready math.

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My 3D Print Scale Calculator

Measurement method

Material compensation

Add a slight percentage bump for cooling contraction in PLA or PETG.

Type this into your slicer
114.3%

28mm → 32mm · Eye Level

32.0 ÷ 28.0 × 100

Tested on Bambu A1 MiniMy Methodology

Conversion logic assumes a 175 human baseline. Eye Level measures to 160cm. Top of Head accounts for hair and helmets at 175cm.
Tip: Always use Uniform Scaling (lock X, Y, Z axes) in Chitubox or Lychee to avoid model distortion.

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Get the Offline Batch Scale Queue Toolkit

Got dozens of STL parts to scale for an entire army? Instead of calculating files one-by-one, grab my standalone offline HTML/JS toolkit. It runs locally on your computer with zero installation, zero internet required, and zero security blocks.

SAMPLE BATCH TOOL OUTPUTINSTANT CHECKLIST (.TXT EXPORT)

[1] File: Hero_Torso_Default.stl

Conversion: 28mm -> 32mm (EYE) • SLICER UNIFORM SCALE: 114.3%

[2] File: Hero_Legs_Default.stl

Conversion: 28mm -> 32mm (EYE) • SLICER UNIFORM SCALE: 114.3%

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* Note: Because I'm setting this up fresh as an independent hobbyist, purchases go through my Ko-fi shop. Think of it as buying me a coffee to support the site—plus you get the offline batch utility as a thank you!

How I use the calculator for every print

  1. 1

    Pick the scales

    Check what scale the sculptor modeled in — usually listed on Patreon or MyMiniFactory — then select the target scale for your army.

  2. 2

    Copy the exact percentage

    Eyeballing percentages leads to distorted proportions. The calculator gives exact mathematical output verified with physical calipers.

  3. 3

    Paste and lock axes

    Enter the percentage into Lychee or Chitubox, lock X, Y, and Z to uniform scaling, and slice.

The conversions I use most often

Before committing a miniature to a long print, verify the scale first. These are the percentages used in my own printing queue.

View full miniature size chart

Questions I get asked about scaling

Straight answers from my own experience at the painting desk.

What scale is modern sci-fi epic wargame miniatures?

Most people in the hobby treat modern sci-fi epic wargame 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.

How do I convert 28mm to 32mm for classic fantasy RPG?

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.

Does material shrinkage affect FDM miniatures?

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 a digital caliper — I use a PARKSIDE with 0.01mm resolution, costs under 15 euro and does the job perfectly.

What is the difference between 28mm and 32mm miniatures?

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.

The flagship modern sci-fi epic wargame uses 32mm heroic scale. A lot of fantasy RPG miniatures are closer to 28mm true scale, though it varies by manufacturer.

How do I scale an STL file in my slicer?

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.

What does 1:56 scale mean in miniature gaming?

1:56 is a ratio scale common in historical wargaming, including WWII platoon wargame. 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: September 14, 2026

Why I Built STLACCESS

I started 3D printing back in 2017 with a cheap entry-level FDM printer. In 2019, I ran a commercial print service in Enschede, Netherlands, but quickly realized running commercial queues drained the fun out of the hobby. I shut it down and returned strictly to hobby printing on a Bambu Lab A1 Mini.

The frustration with miniatures scaling incorrectly led me to pull out digital calipers and work out the exact mathematical percentages. Every formula here is tested on my own printer to ensure proxies match existing tabletop units.

This calculator runs entirely in your browser. I never see your files.