Free Tool

Video File Size Calculator

Name: Video File Size Calculator
Author: ClipVerdict

Estimate file size by resolution, codec, frame rate, and duration. Works for H.264, H.265, ProRes, RAW, AV1, DNxHR — instantly in your browser.

Calculate Video File Size

Free · No signup

Resolution

Codec / Format

Frame Rate

Duration

hoursminutesseconds

Estimated file size

—

Bitrate used

—

Duration

—

Size in MB

—

Size in GB

—

Same duration — codec comparison

Estimates based on typical bitrates for each codec and resolution tier. Actual file sizes vary by camera, encoder settings, scene complexity, and motion. Use for planning purposes — verify against your specific camera or export settings before finalizing storage budgets.

How Video File Size Is Calculated

Video file size is bitrate × duration. The formula:

        File size (GB) = Bitrate (Mbps) × Duration (seconds) ÷ 8 ÷ 1000
      

The codec determines the bitrate required to achieve a given quality level. H.264 and H.265 use inter-frame compression — they only store differences between frames. ProRes stores far more data per frame for easier editing. RAW stores unprocessed sensor data with almost no compression.

Reference bitrates by codec and resolution

Codec	1080p 30fps	4K 30fps	Notes
H.264 (medium)	15–25 Mbps	50–80 Mbps	Most camera and YouTube delivery footage
H.265 / HEVC	8–15 Mbps	25–50 Mbps	~50% smaller than H.264 at similar quality
AV1	6–12 Mbps	20–40 Mbps	Efficient delivery, slow to encode
ProRes 422	147 Mbps	588 Mbps	Apple editing format, fixed bitrates
ProRes 4444	330 Mbps	1,320 Mbps	VFX and compositing
DNxHR SQ	145 Mbps	580 Mbps	Avid editing format
ARRIRAW	N/A	~2,000+ Mbps	Cinema camera RAW

Storage planning rule of thumb

1 TB handles approximately

20 hours of 1080p H.264
5 hours of 4K H.264
2 hours of 4K H.265
25 minutes of 4K ProRes 422
8 minutes of 4K ProRes 4444

Budget storage at 3× footage

Original footage
+ Proxy files
+ Rendered output
+ Project files & assets
= 3–4× raw footage size

Proxy tip: if your storage is limited, proxy workflows dramatically reduce the storage footprint of your editing drive. Proxies are low-resolution stand-ins used for editing — the full-resolution files are only read during final export. Both DaVinci Resolve and Premiere Pro have built-in proxy generation.

Frequently Asked Questions

How do you calculate video file size?

Video file size is bitrate × duration. File size (GB) = Bitrate (Mbps) × Duration (seconds) ÷ 8 ÷ 1000. Bitrate depends on codec, resolution, and frame rate. ProRes and RAW codecs use far higher bitrates than H.264 or H.265 at equivalent quality because they apply less compression.

How large is 1 hour of 4K video?

Codec determines everything. One hour of 4K H.264 is approximately 25–50 GB. One hour of 4K H.265 is roughly 15–30 GB. One hour of 4K ProRes 422 is approximately 200–400 GB. One hour of 4K RAW is 300 GB or more. Use the calculator above with your specific settings.

Why does codec matter so much for file size?

Codecs use very different compression strategies. H.264 and H.265 only store changes between frames (inter-frame compression), achieving small files. ProRes stores more data per frame for easier editing. RAW stores unprocessed sensor data with almost no compression. A ProRes file can be 10–20× larger than H.264 at similar visual quality.

How much storage do I need for video editing?

Plan for at least 3× your footage size: original files, proxy files, and rendered output. 1 TB handles approximately 20 hours of 1080p H.264, 5 hours of 4K H.264, or 25 minutes of 4K ProRes 422.

What is bitrate in video?

Bitrate is the amount of data per second of video, measured in megabits per second (Mbps). Higher bitrate means more data and generally better quality but larger files. YouTube 4K targets 35–45 Mbps. ProRes 422 at 4K runs at about 588 Mbps. The codec determines how efficiently that bitrate translates to visual quality.