# Model Scale Calculator

> HO, N, O, 1:35, 28mm & more

Canonical page: [https://chrome-stats.com/d/id6797369448](https://chrome-stats.com/d/id6797369448)

## Overview

- **ID:** `id6797369448`
- **Platform:** Apple
- **Type:** Apple app
- **Status:** Available
- **Publisher:** Harbor Apps LLC
- **Category:** Utilities
- **Version:** 1.0
- **Last updated:** 2026-08-26
- **First published:** 2026-08-26
- **Size:** 3.99 MB
- **Data as of:** 2026-09-22
- **Store listing:** [Apple App Store](https://apps.apple.com/us/app/model-scale-calculator/id6797369448)
- **Website:** [https://model-scale-calculator.harborapps.org](https://model-scale-calculator.harborapps.org/)
- **Privacy policy:** [https://model-scale-calculator.harborapps.org/privacy](https://model-scale-calculator.harborapps.org/privacy)

## Description

Pick a scale, type a dimension, read the answer as you type. Real to model, model to real, and “what scale is this?”

A scale converter for people who build models.

Pick a scale — HO, N, O, 1:35 armour, 28mm heroic, 1/4" = 1' — type a dimension, and read the answer as you type. Free, offline, no account, no ads.

THREE ANSWERS, ONE SCREEN

• Real → model — how big is a 40-foot boxcar in HO?
• Model → real — this part measures 92 mm; what is that full size?
• What scale is this? — give a real length and the model length it has to come out at, and get the ratio.

COMPARE ACROSS SCALES

A second view takes one measurement and shows it in every scale in a hobby group at once — model railway gauges, military armour, aircraft, tabletop miniatures — with a proportional bar per row so you can judge the sizes by eye instead of reading numbers.

UNITS HOBBYISTS ACTUALLY TYPE

It parses what you would write on a workbench note: 250mm, 2.5 cm, 5' 6", 5ft 6in, 1 1/2", 3/4", 1-1/2". Feet-and-inches and fractional inches are first-class output formats, not an afterthought — fractions come back as fractions, rounded to the precision you choose.

SCALES INCLUDED

• Model railways — Z, N, TT, HO, OO, S, O, G and more
• Military and armour — 1:16, 1:35, 1:48, 1:72
• Aircraft — 1:32, 1:48, 1:72, 1:144
• Cars — 1:18, 1:24, 1:43, 1:64
• Tabletop and wargaming — 15mm, 28mm heroic, 32mm, 54mm
• Architecture — imperial drawing scales like 1/4" = 1' and metric 1:50, 1:100
• Any custom ratio you type

WORKS COMPLETELY OFFLINE

No account, no sign-in, no sync, no paywall and no advertising. Every calculation happens on your device, and nothing you type is ever sent anywhere. The only thing the app ever sends is anonymous usage data — which scales and modes get used — and you can switch that off in Settings.

For model railroaders, scale modellers, miniature painters, RC builders, dollhouse makers, architects and anyone who has ever stood in a hobby shop doing long division on their phone.

## Rankings

- #1,721,508 — Overall

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Source: [Chrome-Stats](https://chrome-stats.com/d/id6797369448)