Video File Size Calculator – Estimate Storage & Compression

Use this Calculator to estimate your video's storage needs based on resolution, frame rate, and compression settings. Select a common video format below to pre-fill recommended settings or customize everything yourself.

Popular Video Formats:

Overview

This calculator helps you estimate how large your video file will be. Several things affect the final size:

1. Frame Size

   • This refers to the width and height (in pixels) of your video.
   • Example: If your video is 1920 x 1080 (Full HD), you multiply 1920 by 1080 to get 2,073,600 pixels per frame.

2. Video Codec (e.g., H.264/MPEG-4 AVC)

   • A codec compresses your video to save space.
   • Example: H.264 can reduce file size by around 30% to 67%, depending on the content.
   • The exact savings depend on how the codec compresses each scene.
   • Some codecs only work with specific chroma subsampling (e.g., 4:2:0 for most H.264 implementations).
   • Certain codecs limit bit depth (e.g., many “consumer” codecs are 8-bit only, while professional codecs can handle 10-bit or higher).
   • The color channels (RGB vs. YCbCr) and even the maximum resolution or frame rate may also be determined by the codec’s capabilities.

3. Codec Compression Factor This number indicates how much the chosen codec reduces file size compared to a fully uncompressed version at the same resolution, frame rate, color depth, and chroma subsampling.

   • A 1× factor means “no compression”—the file is the same size as uncompressed.
   • A 5× factor means the codec produces files roughly 1/5 the size of uncompressed.
   • Different codecs achieve different compression factors. For example, an H.265/HEVC codec might achieve a higher factor (much smaller files) than MPEG-2 at the same quality level.
   The larger this factor, the smaller the resulting file—assuming you keep the same resolution, frame rate, and color settings. If you change codecs, you usually change this factor, because every codec has its own efficiency and compression strategy.

   Note: Compression factors and percentage reductions refer to the same concept but expressed differently. A 5× compression factor means the file is 1/5 the original size, which equals an 80% size reduction. Higher compression factors result in smaller files.

4. User‐Entered Bit Rate (“Clamp”)

   This sets a maximum data rate the encoder can use (e.g., 25 Mbps).

   • Fixed data per second: Regardless of resolution or frame rate, the codec won’t exceed this rate.
   • Quality vs. Bit Rate: Increasing resolution or frame rate at the same bit rate usually lowers quality (because the same bits are spread over more pixels/frames).
   • File Size: The total file size is roughly “bit rate × duration,” so higher bit rates generally mean bigger files—and potentially better quality.
   • Typical broadcast or disc standards also have bit rate limits (e.g., ~40 Mbps for standard Blu‐ray video). If you exceed them, the file may not play on certain devices.
   • File Size Calculation: Total file size (in bytes) = (bit rate in bits/second × duration in seconds) ÷ 8. This gives you the baseline file size when bit rate is the limiting factor.

5. Color Channels

   • Black-and-white (grayscale) has just one channel—it only stores brightness information.
   • RGB (red, green, blue) has three channels, which store different color information for each pixel.
   • YCbCr (commonly used in digital video) also uses three channels but in a different way—one channel for brightness (Y) and two for color differences (Cb and Cr).
   • The more channels there are, the more data each pixel needs, and the larger the file becomes. For example, a black-and-white video (one channel) naturally requires less data than a full-color RGB video (three channels).

6. Chroma Subsampling (4:4:4, 4:2:2, etc.)

   • This describes how much color information is stored relative to brightness information.
   • The notation represents sampling ratios for luminance (Y) and chrominance (Cb, Cr) components:
     • 4:4:4 means full color resolution—color is sampled at the same rate as brightness (no color compression).
     • 4:2:2 means color is sampled at half the horizontal resolution of brightness (moderate color compression).
     • 4:2:0 means color is sampled at half resolution both horizontally and vertically (high color compression).
   • DVDs and Blu-ray discs typically use 4:2:0, while professional video often uses 4:2:2.
   • Key point: More color data (like 4:4:4) gives higher quality but needs more storage.

7. Color Depth (8-bit vs. 10-bit)

   • 8-bit color can show 256 shades per color channel and is common in consumer video.
   • 10-bit color can show 1024 shades per channel, which provides more detail (especially during color adjustments), but it increases file size.

8. Frame Rate (fps)

   • This is how many frames (pictures) per second your video has (e.g., 24, 30, 60 fps).
   • Higher frame rates = more frames per second = larger file size.

9. Running Time (Duration)

   • The longer your video, the more total data you’ll generate.

Putting It All Together

All these factors—frame size, color channels, chroma subsampling, bit depth, frame rate, codec, and running time—add up to influence the file size. They also affect the bit rate, which is how quickly your computer or storage device must handle data.

By adjusting these elements (for example, choosing a lower resolution or a codec that compresses more), you can reduce the file size—just be aware that this may lower video quality.