Whether you are exporting video projects from Adobe Premiere or DaVinci Resolve, configuring live streaming encoders like OBS Studio, or managing cloud storage for archival media, understanding video bitrate mathematics is essential.
Bitrate—measured in Megabits per second (Mbps) for video and kilobits per second (kbps) for audio—is the single most significant factor determining both video visual fidelity and final exported file size.
Calculate exact video file sizes and bandwidth requirements: thetoolss.com/tool/video-bitrate-file-size-calculator
The Fundamental Video File Size Formula
The mathematical relationship governing all uncompressed and compressed digital video is: File Size (Megabytes) = (Video Bitrate in Mbps + Audio Bitrate in Mbps) * Duration in Seconds / 8
Because there are 8 bits in a byte, a 15-minute video rendered at 10 Mbps video bitrate with 192 kbps audio will produce:
- (10 + 0.192) * 900 seconds / 8 ≈ 1,146 MB (~1.12 GB).
Recommended Bitrates for Modern Video Codecs (H.264 / H.265 HEVC / AV1)
- 1080p Full HD (30 fps): 6–8 Mbps for YouTube web uploads; 4–6 Mbps for live streaming on Twitch or YouTube Live.
- 1080p Full HD (60 fps): 9–12 Mbps.
- 4K Ultra HD (30 fps): 35–45 Mbps for H.264; 20–25 Mbps for modern HEVC / AV1.
- 4K Ultra HD (60 fps): 50–65 Mbps.
- Audio Streams: 128 kbps (Voice / Podcasts), 192–256 kbps (High Fidelity Music), 320 kbps (Studio Master).
Planning Timelapse Photography Intervals and Storage
Timelapse cinematography compresses hours of real-time events into a brief 30-second clip. Choosing the correct interval between shutter actuations ensures silky smooth motion without exhausting camera SD card storage. Calculate timelapse interval seconds and storage: thetoolss.com/tool/timelapse-frame-interval-calculator
Scaling Aspect Ratios Dynamically
When preparing video thumbnails or reformatting widescreen landscape 16:9 footage into vertical 9:16 reels for TikTok or Instagram, maintaining proportional pixel dimensions prevents distortion. Scale dimensions while preserving aspect ratio: thetoolss.com/tool/aspect-ratio-dimension-scaler