Metric to SAE Calculator

The SAE system of measurement units is a collection of measurement units, a subsystem of the imperial system used by American engineers, mechanics, and hobbyists: SAE stands for society of automotive engineers.

SAE units are widely used to measure machines, mechanical components, screws, and bolts. A measurement in SAE units corresponds to a measurement in inches (most often) or feet but is almost always expressed as fraction: in the following sections we will teach you how to calculate the conversion from metric to SAE, and we will show you the metric to SAE chart for a quick, at-a-glance conversion of bolt sizes and much more!

To convert from metric to SAE, you only need to learn a simple conversion between metric and imperial units. In most situations, you will have to convert millimeters to inches since these are the units most commonly used:

You can calculate the metric to SAE conversion between other units by using the following rules:

The story is different (and easier) within the metric system:

However, the result of this conversion is not exactly what we need in most situations! Bolt, nut, and screw sizes come in standardized sizes: , , and , and so on; to understand quickly which wrench to use you may have more luck using a metric to SAE chart.

Our calculator for the metric to SAE conversion gives you the result you deserve but not the result you need. In your toolbox, you will find wrenches and keys of slightly different sizes, often marked with neat ratios like and . Using a metric to SAE chart, you can quickly find the best fitting SAE wrench for a metric bolt, and vice-versa. Here is it:

Discover more conversion between and within the imperial and metric systems with our suite of dedicated tools:

• The conversion calculator;
• The imperial to metric conversion;
• The metric converter;
• The metric to standard converter;
• The imperial converter;
• The metric to imperial converter; and
• The measurement converter.