Video File Size & Bitrate Estimator
Plan your storage or optimize your stream. Instantly calculate video file sizes based on bitrate, or find the perfect bitrate for a target size.
Estimating video parameters...
Enter video details to estimate storage requirements or encoding settings.
Mastering Video Encoding: Size vs. Bitrate
Whether you are preparing a video for YouTube, live streaming on Twitch, or archiving your personal library, understanding the relationship between duration, bitrate, and file size is crucial. A well-optimized video balances visual fidelity with storage efficiency, ensuring fast uploads and smooth playback for your audience.
How Bitrate Affects Quality
Bitrate is the amount of data processed per unit of time (usually measured in Mbps). A higher bitrate typically means higher visual quality, but it also results in larger file sizes. If your bitrate is too low, the video will appear blocky or "pixelated" during fast-motion scenes. If it is too high, you are wasting bandwidth and storage space without a perceivable gain in quality.
Streaming Optimization
Platforms like Twitch have strict maximum bitrates (e.g., 6000kbps). Our calculator helps you find the right balance for your upload speed to prevent buffering for your viewers.
Storage Planning
Recording in high-quality formats like ProRes can consume hundreds of gigabytes per hour. Use our estimator to plan your hard drive or cloud storage needs before you start a large project.
Understanding Video Codecs
- H.264 / AVC: The industry standard for the last decade. It is compatible with almost every device but is less efficient than modern alternatives.
- H.265 / HEVC: The successor to H.264. It provides the same visual quality at roughly 50% of the file size. Ideal for 4K and HDR content.
- AV1: The new open-source codec designed for the future of the internet. It is even more efficient than HEVC and is being adopted by YouTube and Netflix.
External Encoding Resources
- YouTube Recommendations: Official bitrate and resolution guidelines for high-quality uploads.
- Twitch Help Center: Learn about Twitch stream settings and ingest limits.
- HandBrake: A powerful, open-source tool for converting video and optimizing bitrates. Get it at HandBrake.fr.
Frequently Asked Questions
What is CBR vs. VBR?
Constant Bitrate (CBR) stays the same throughout the video, which is good for live streaming. Variable Bitrate (VBR) adjusts based on the complexity of the scene, saving space for simple scenes and providing more data for complex ones.
Does audio affect the file size?
Yes, though much less than video. A standard 128kbps stereo track adds about 57MB per hour to your file size. Our calculator includes this overhead in its estimates.
How do I calculate bitrate for a specific file size?
Switch our tool to "Target Bitrate" mode, enter your video duration and the size of your storage medium (like a 4.7GB DVD), and we will tell you the exact maximum bitrate you can use.
Pro Tip: When in doubt, it is usually better to record at a higher bitrate and compress later using a multi-pass VBR encoder.