body {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
line-height: 1.6;
color: #333;
margin: 0;
padding: 0;
}
.calculator-container {
max-width: 800px;
margin: 40px auto;
padding: 30px;
background: #ffffff;
border-radius: 12px;
box-shadow: 0 4px 20px rgba(0,0,0,0.1);
border: 1px solid #e0e0e0;
}
.calculator-title {
text-align: center;
color: #2c3e50;
margin-bottom: 30px;
font-size: 28px;
font-weight: 700;
}
.input-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
margin-bottom: 25px;
}
.input-group {
display: flex;
flex-direction: column;
}
.input-group label {
font-weight: 600;
margin-bottom: 8px;
color: #555;
}
.input-group input, .input-group select {
padding: 12px;
border: 2px solid #ddd;
border-radius: 8px;
font-size: 16px;
transition: border-color 0.3s;
}
.input-group input:focus, .input-group select:focus {
border-color: #3498db;
outline: none;
}
.calc-btn {
width: 100%;
padding: 15px;
background: linear-gradient(135deg, #3498db, #2980b9);
color: white;
border: none;
border-radius: 8px;
font-size: 18px;
font-weight: bold;
cursor: pointer;
transition: transform 0.1s, opacity 0.2s;
}
.calc-btn:hover {
opacity: 0.9;
}
.calc-btn:active {
transform: scale(0.98);
}
.results-area {
margin-top: 30px;
background: #f8f9fa;
padding: 20px;
border-radius: 8px;
border-left: 5px solid #3498db;
display: none;
}
.result-row {
display: flex;
justify-content: space-between;
margin-bottom: 12px;
padding-bottom: 12px;
border-bottom: 1px solid #e9ecef;
}
.result-row:last-child {
border-bottom: none;
margin-bottom: 0;
padding-bottom: 0;
}
.result-label {
color: #666;
font-weight: 500;
}
.result-value {
font-weight: 700;
color: #2c3e50;
font-size: 18px;
}
.article-section {
max-width: 800px;
margin: 50px auto;
padding: 0 20px;
}
h2 {
color: #2c3e50;
margin-top: 40px;
border-bottom: 2px solid #eee;
padding-bottom: 10px;
}
p {
margin-bottom: 20px;
}
ul {
margin-bottom: 20px;
}
li {
margin-bottom: 10px;
}
.note {
background-color: #fff3cd;
border: 1px solid #ffeeba;
color: #856404;
padding: 15px;
border-radius: 5px;
margin-bottom: 20px;
}
@media (max-width: 600px) {
.input-grid {
grid-template-columns: 1fr;
}
}
function calculateFrameRateLogic() {
var shootFps = parseFloat(document.getElementById('shootFps').value);
var projectFps = parseFloat(document.getElementById('projectFps').value);
var originalDuration = parseFloat(document.getElementById('clipDuration').value);
var type = document.getElementById('calculationType').value;
var resultsDiv = document.getElementById('results');
if (isNaN(shootFps) || isNaN(projectFps) || isNaN(originalDuration)) {
alert("Please enter valid numbers for FPS and Duration.");
return;
}
if (shootFps <= 0 || projectFps <= 0 || originalDuration projectFps) {
effect = "Slow Motion (" + factor.toFixed(2) + "x slower)";
} else if (shootFps < projectFps) {
effect = "Fast Motion / Timelapse (" + (projectFps/shootFps).toFixed(2) + "x faster)";
} else {
effect = "Real-Time (No Change)";
}
} else {
// Real-time Calculation
// Just playing the clip at normal speed, regardless of framerate mismatch
speedPercent = 100;
newDuration = originalDuration;
effect = "Real-Time (Frames Skipped or Duplicated)";
factor = 1;
}
// Display Results
document.getElementById('playbackSpeed').innerHTML = speedPercent.toFixed(2) + "%";
document.getElementById('effectType').innerHTML = effect;
document.getElementById('newDuration').innerHTML = newDuration.toFixed(2) + " seconds";
document.getElementById('stretchFactor').innerHTML = "1:" + factor.toFixed(2);
document.getElementById('totalFrames').innerHTML = totalFrames.toLocaleString() + " frames";
resultsDiv.style.display = "block";
}
Understanding Frame Rate and Video Speed
Frame rate, measured in Frames Per Second (FPS), is the frequency at which consecutive images (frames) appear on a display. It is the heartbeat of video production, dictating not just the smoothness of motion but also the perception of time.
When you record video, you are capturing a specific number of images every second. When you play that video back, the speed at which those images are displayed relative to how they were captured determines if the footage looks like real-time, slow motion, or fast motion (time-lapse).
How the Calculation Works
This Frame Rate Speed Calculator helps videographers and editors determine how clip duration and playback speed change when "conforming" footage. Conforming is the process of telling your editing software to interpret the frames of a clip at a different rate than they were shot.
Formula:
Playback Speed % = (Timeline FPS / Shooting FPS) × 100
New Duration = Original Duration × (Shooting FPS / Timeline FPS)
Example: The "Cinematic" Slow Motion
A very common technique in filmmaking is shooting at a higher frame rate to achieve smooth slow motion.
- Shooting FPS: 60 FPS (capturing 60 images per second).
- Project FPS: 24 FPS (standard cinematic playback).
If you play the 60 frames you captured in one second on a 24 FPS timeline, it will take 2.5 seconds to show all the images (60 / 24 = 2.5). This results in footage that moves 2.5 times slower than reality, or at 40% speed.
Common Frame Rate Standards
Choosing the right frame rate before you hit record is crucial for post-production.
- 24 FPS (23.976): The standard for movies and cinema. It provides a natural motion blur that feels "film-like."
- 30 FPS (29.97): Standard for television broadcasts (NTSC) and online video. It looks slightly smoother and more "realistic" than 24 FPS.
- 60 FPS: Often used for sports, gaming, and reality TV because it captures crisp movement. It is also the entry-level standard for slow motion when slowed down to 24 or 30 FPS.
- 120 FPS / 240 FPS: High-speed frame rates dedicated to extreme slow motion. Shooting 120 FPS for a 24 FPS timeline slows time down by a factor of 5.
Real-Time vs. Conformed Playback
In video editing software like Adobe Premiere Pro, DaVinci Resolve, or Final Cut Pro, you have two choices when dealing with mismatched frame rates:
- Real-Time (Drop/Skip): The software tries to keep the duration the same. If you put a 60 FPS clip on a 30 FPS timeline, the software simply throws away every other frame. The video plays at normal speed, but you lose the smoothness of the high frame rate.
- Conformed (Interpret Footage): You tell the software to play every single frame you shot, but at the project's speed. This stretches the clip out, creating slow motion without any stuttering or "ghosting."
Why Calculate This?
Professional editors use this calculator to plan their timeline. If a director asks, "We need a 5-second slow-motion shot of the product," the camera operator needs to know exactly how long to roll the camera.
For example, if you are shooting 120 FPS for a 24 FPS commercial, and you need 5 seconds of finished slow-motion footage, you only need to record 1 second of real-time action.