This calculator is designed for gamers (FPS), airsoft enthusiasts, paintball players, and ballistic technicians to determine the cyclic rate of fire of a weapon or marker. By measuring the number of rounds discharged over a specific time period, you can accurately calculate the Rounds Per Minute (RPM) and Rounds Per Second (RPS).
How to Calculate Fire Rate (RPM)
The standard measure for fire rate is RPM (Rounds Per Minute). However, since most magazines empty in just a few seconds, it is rarely practical to fire for a full minute to test. Instead, we measure a burst and extrapolate the data.
The Formula:
RPM = (Rounds Fired ÷ Time in Seconds) × 60
Understanding the Metrics
RPM (Rounds Per Minute): The theoretical number of shots the weapon could fire in one minute if it had an infinite magazine and no overheating.
RPS (Rounds Per Second): The frequency of fire per second. This is often used in airsoft and paintball (e.g., "This build shoots 30 RPS").
Cycle Time (ms): The time in milliseconds between each shot. This is crucial for frame-data analysis in video games (Call of Duty, Battlefield, etc.).
Common Fire Rates Comparison
Weapon Type
Typical RPM
Typical RPS
Slow Automatic (e.g., AKM / Grease Gun)
450 – 600 RPM
7.5 – 10 RPS
Standard Assault Rifle (e.g., M4A1)
700 – 950 RPM
11.6 – 15.8 RPS
High Rate SMG (e.g., Vector / MP7)
950 – 1200 RPM
15.8 – 20 RPS
Rotary Cannon (e.g., Minigun)
3,000 – 6,000 RPM
50 – 100 RPS
Why Measure Cycle Time?
In competitive gaming, fire rate is often tied to the game's frame rate. If a weapon's fire rate doesn't align well with the server tick rate or the frame rate (e.g., 60Hz), shots might be "lost" or registered in the next packet, affecting Time-To-Kill (TTK). Knowing the exact millisecond delay between shots (Cycle Time) helps in understanding recoil patterns and damage output potential.
function calculateRPM() {
// 1. Get input elements using exact IDs
var roundsInput = document.getElementById('frc_rounds');
var timeInput = document.getElementById('frc_time');
var resultBox = document.getElementById('frc_results');
// 2. Parse values
var rounds = parseFloat(roundsInput.value);
var time = parseFloat(timeInput.value);
// 3. Validation
if (isNaN(rounds) || isNaN(time) || time <= 0 || rounds 0) {
cycleTime = 1000 / rps;
}
// 5. Update UI
document.getElementById('res_rpm').innerHTML = Math.round(rpm).toLocaleString() + " RPM";
document.getElementById('res_rps').innerHTML = rps.toFixed(2) + " RPS";
document.getElementById('res_cycle').innerHTML = cycleTime.toFixed(1) + " ms";
// 6. Show results
resultBox.style.display = "block";
}