Video File Size Calculator

About the Video File Size Calculator

Video file sizes can range from megabytes to terabytes depending on resolution, bitrate, codec, and duration. Whether you're planning storage for security cameras, estimating upload times for YouTube, calculating streaming bandwidth needs, or managing a video production workflow, knowing file sizes in advance is essential. The Video File Size Calculator gives you instant estimates based on your encoding parameters.

Video bitrate is the primary determinant of file size and quality. A 1080p video at 8 Mbps looks great for streaming but produces 3.6 GB per hour. The same video at 2 Mbps would be only 900 MB but visibly lower quality. Modern codecs like H.265/HEVC and AV1 achieve the same perceived quality at 30-50% lower bitrate than H.264, significantly reducing file sizes.

This calculator handles all common scenarios: enter duration and bitrate for a quick estimate, or specify resolution and quality level for codec-aware calculations. It includes audio track sizing, multi-camera calculations, and upload/download time estimates based on your internet speed.

When This Page Helps

Use this calculator when you need a realistic storage, upload, or streaming estimate before you export or record video. It is useful for creators, editors, and security-camera planning because bitrate and duration turn into hard drive space quickly. It also helps you compare codec choices before you commit to an encode preset.

How to Use the Inputs

1. Enter video duration in hours, minutes, and seconds
2. Select resolution or enter a custom bitrate
3. Choose the codec (H.264, H.265, VP9, AV1, ProRes)
4. Select quality level (low, medium, high, or custom bitrate)
5. Optionally add audio track parameters
6. Review file size, storage needs, and transfer time estimates

Example Calculation

Tips & Best Practices

• H.265 gives 30-50% smaller files but takes 3-5× longer to encode than H.264
• Audio is typically only 3-5% of total file size — don't obsess over audio compression
• Use variable bitrate (VBR) encoding for better quality-to-size ratio than constant bitrate
• For web delivery, target the lowest bitrate that looks acceptable — most viewers won't notice
• ProRes/DNxHR files are 5-10× larger than H.264 but are needed for professional editing
• YouTube re-encodes everything — upload at high quality and let YouTube handle delivery

Understanding Video Codecs

H.264 (AVC) remains the most universally compatible codec — every device and browser supports it. H.265 (HEVC) offers 30-50% better compression but has licensing complexities and isn't supported in all browsers. VP9 is Google's royalty-free codec used by YouTube. AV1 is the newest open codec with the best compression ratios but requires the most encoding time.

For production workflows, ProRes (Apple) and DNxHR (Avid) provide high-quality intermediate codecs optimized for editing — they decode fast but produce very large files (50-200 Mbps for 1080p). These are delivery or editing formats, never used for streaming.

Resolution and Bitrate Guidelines

Resolution determines the pixel grid; bitrate determines how much data represents those pixels. Common pairings: 720p at 2-5 Mbps, 1080p at 4-10 Mbps, 1440p at 8-15 Mbps, 4K at 15-40 Mbps. These are for H.264 streaming — reduce by 30-40% for H.265 at equivalent quality.

Content complexity matters enormously. A static PowerPoint presentation at 1080p might look perfect at 1 Mbps. A fast-action game capture at the same resolution might need 15 Mbps to avoid compression artifacts (blocking, banding, mosquito noise). Professional broadcast typically uses 20-50 Mbps for 1080p.

Storage Planning for Video Libraries

For video producers or security installations, storage planning must account for growth. A YouTube creator producing 3 hours of 4K content per week at 50 Mbps archival quality needs about 135 GB/week or 7 TB/year. Security cameras running 24/7 at motion-triggered 1080p H.265 typically consume 500 GB-1.5 TB per camera per month. Always plan for 30% growth margin and consider tiered storage (SSD for active projects, HDD for archive).

Frequently Asked Questions

• What bitrate should I use for 1080p?

  For streaming: 4-8 Mbps (H.264) or 3-5 Mbps (H.265). For archival/editing: 20-50 Mbps. YouTube recommends 8 Mbps for 1080p SDR uploads. For 4K, double or triple these values. Lower motion content (lectures) needs less bitrate than high-motion (sports, gaming).

• How much smaller is H.265 vs H.264?

  H.265/HEVC typically achieves 30-50% smaller files at the same visual quality as H.264. AV1 achieves similar or better compression than H.265. VP9 (YouTube) is roughly comparable to H.265. The tradeoff is longer encoding time for newer codecs.

• How much storage does 24/7 security camera footage need?

  One 1080p camera at 4 Mbps (H.265) uses about 42 GB/day or 1.26 TB/month. Four cameras: 5 TB/month. Most NVRs use motion-triggered recording to reduce this by 50-80%, but always plan for peak usage.

• What is the difference between bitrate and quality?

  Bitrate is the amount of data per second. Quality is the perceived visual result. The same bitrate produces different quality depending on: codec efficiency, resolution, content complexity, and encoding settings (CRF, preset). A static slide show needs much less bitrate than a sports broadcast.

• How long does it take to upload a video?

  Upload time = File Size / Upload Speed. A 3.5 GB file on 10 Mbps upload takes about 47 minutes. On 50 Mbps upload: about 9 minutes. Real upload speeds are typically 60-80% of advertised rates due to overhead and congestion.

• What is CRF and how does it affect file size?

  CRF (Constant Rate Factor) is a quality-based encoding mode where bitrate varies to maintain consistent quality. Lower CRF = higher quality = larger files. For H.264: CRF 18 is visually lossless (~20 Mbps for 1080p), CRF 23 is default (~5 Mbps), CRF 28 is low quality (~2 Mbps).