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Key Features
Instant Calculation
Get accurate results in real time with our optimized algorithm.
Mobile Friendly
Fully responsive design. Works on all devices & screen sizes.
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100% Free
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Scale models, maps, and blueprints all use a scale ratio (like 1:24 or 1/100) relating a small model/map distance to the real-world distance it represents. Given any two of {real-world distance, model/map distance, scale ratio}, this tool solves for the third.
How it works
A scale of "1:N" means 1 unit of model/map distance represents N of the same unit in real life, so real = model × N and model = real ÷ N. Scale ratios can be entered as either "1:24" or "1/24" notation.
- Enter what are you solving for?.
- Enter real-world distance.
- Enter real-world distance unit.
- Enter model/map distance.
- Enter model/map distance unit.
- Enter scale (e.g. 1:24 or 1/24).
- Click Calculate to see your results.
Examples
A 1:24 scale model car
A 1-inch model detail on a 1:24 scale model represents 24 inches (2 feet) in real life.
Who should use it
- Figuring out a scale model's real-world dimensions.
- Calculating map distances from a stated scale ratio.
Industry applications
- Model building and hobbyist scale modeling
- Architecture and blueprint reading
- Cartography and surveying
Advantages
- Solves for any of the three unknowns, not just one fixed direction.
- Accepts both "1:24" and "1/24" scale notation.
Limitations
- Assumes a simple linear scale — does not account for non-uniform scaling or perspective distortion in photographs or artistic renderings.
Common mistakes to avoid
- Mixing up which number is model and which is real — in "1:24", the "1" is always the model/map side and the "24" is always the real-world side.
Best practices
- When solving for scale ratio from two known distances, make sure both are measured consistently (e.g. corresponding points on the model and the real object).
Tips
- Common hobby scales include 1:24 and 1:18 (die-cast cars), 1:48 and 1:72 (model aircraft), and 1:87 (HO scale trains) — recognizing these can help sanity-check a calculated scale ratio.