Another RAW Image Calculator
There are a few calculators around and some of them are good but missing DPX, EXR and TIFF on the same page. This image file size calculator will help you estimate the file size of an uncompressed raster image file, provided that you know the image’s resolution and its bit depth.
Why Do We Care About File Size?
Think of file size like the weight of a backpack. If it’s too heavy, you can’t carry it easily. In the world of video and VFX, big files can slow down computers, eat up storage, and choke your internet speed. That’s why professionals calculate file size before starting a project.
Two Main Reasons
- Storage Space
A single 4K frame can be 50–100 MB. A movie has thousands of frames! If you don’t plan, you might run out of disk space halfway through. - Performance & Bandwidth
Big video files are hard to handle, they take longer to load, copy, or stream, and if your network isn’t fast enough, the video will freeze like a bad Facetime call. For example, a standard movie runs at 24 frames per second (fps). If you’re working with DCI 4K resolution (4096 × 2160) at 16-bit color, each frame is about 70 MB. Multiply that by 24 fps, and you need about 1.58 GB every second just to play the video smoothly. Now imagine a 60-minute movie at that size, it would take up 5,695 terabytes of storage! That’s why professionals calculate file size and use compression, otherwise, you’d need a warehouse full of hard drives just for one film.
In Simple Terms
Calculating file size helps you:
- Plan storage (Do you have more than enough disk space?)
- Check speed (Can your computer and network handle it?)
- Avoid surprises (Nobody wants a project that crashes because the files are too big!)
Image file sizes
When we talk about image file sizes, it really comes down to two things: how many pixels the image contains, and how much information is stored in each pixel.
A raster image is made up of pixels, and each pixel carries a certain number of bits. Black-and-white images need very little, often just 1 to 8 bits per pixel, while color images require more detail, typically anywhere from 8 to 64 bits per pixel.
Put simply, the more pixels an image has, and the more data each pixel carries, the larger the file becomes. More detail always means more data, and more data means a bigger file.
Launch the calculator RAW image file size calculator
How to Calculate the Size of DPX and EXR Files
When working with high-resolution image sequences in VFX or post-production, understanding file sizes is critical for storage planning and pipeline optimization. Two common formats in this space are DPX and EXR. Let’s break down how to estimate their sizes.
DPX File Size Calculation
DPX (Digital Picture Exchange) is widely used for film scans and stores uncompressed image data. The size depends on:
- Resolution: Width × Height
- Bit Depth: Typically 10, 12, or 16 bits per channel
- Channels: RGB (3) or RGBA (4)
Formula
File Size = Width × Height × Bits per Channel ÷ 8 × Number of Channels
Example
For a 4K DPX frame (4096 × 3112), 10-bit RGB:
Size = 4096 × 3112 × 10 ÷ 8 × 3 ≈ 47 MB per frame
Multiply by the number of frames for sequence size.
EXR File Size Calculation
EXR (OpenEXR) is more flexible and supports:
- Compression (ZIP, PIZ, DWAA, etc.)
- Variable bit depth (16-bit half-float, 32-bit float)
- Multiple channels (RGB, Alpha, Z-depth, etc.)
For uncompressed EXR:
File Size = Width × Height × Bytes per Channel × Number of Channels
- Bytes per Channel: 2 for half-float (16-bit), 4 for float (32-bit)
Example
4K EXR (4096 × 3112), 16-bit half-float RGB:
Size = 4096 × 3112 × 2 × 3 ≈ 76 MB per frame
With compression, sizes vary dramatically, often 2–10× smaller depending on image content.
Quick Reference Table
| Format | Resolution | Bit Depth | Channels | Approx Size |
|---|---|---|---|---|
| DPX | 4K | 10-bit | RGB | ~47 MB |
| EXR | 4K | 16-bit | RGB | ~76 MB |
Pro Tip: Always factor in compression for EXR when planning storage,it can save terabytes on large project
Launch the calculator RAW image file size calculator