Hunting Unit Converters

Grains ↔ grams, fps ↔ m/s, yards ↔ meters, ft-lb ↔ joules — exact physical conversions.

Free, no sign-upUpdated September 2026

How this works

1 grain = 0.0648 g  ·  1 fps = 0.3048 m/s  ·  1 yard = 0.9144 m  ·  1 ft-lb = 1.3558 joules

These are exact, internationally defined physical unit conversions — not estimates or approximations. Grains to grams and yards to meters both come from fixed definitions of the imperial units in terms of the metric system.

Where hunters run into mixed units

US hunters mostly work in grains, feet per second, yards, and foot-pounds, while European ammunition boxes, ballistic software defaults, and hunting regulations in many countries use grams, meters per second, meters, and joules. This calculator is built for quickly translating between the two systems, whether you're reading an imported cartridge's spec sheet or converting your own trajectory numbers for a hunt abroad.

Frequently asked questions

Why would I need to convert grains to grams for hunting?

Many European and international ammunition manufacturers publish specs in metric units (grams, meters per second, joules) rather than the grains, fps, and ft-lb used in most US load data — this bridges the two systems.

Are these conversions exact or approximate?

Exact — these come from fixed, internationally defined relationships between the imperial and metric units, not estimates or rounded approximations.

Can I convert multiple values at once?

Yes — each of the four conversions (grains, fps, yards, ft-lb) has its own input field, so you can convert all four at once rather than one at a time.