Video Recording Storage Calculator – Bitrate & Record Time

How the Video Recording Storage Calculator Works

The Video Recording Storage Calculator estimates recording file size from:

• recording duration;
• average video bitrate;
• optional audio bitrate;
• file-overhead allowance;
• number of identical clips.

It supports two calculation methods:

The calculator can also compare the resulting storage requirement with a memory card, SSD, or drive capacity.

Use known-bitrate mode whenever a representative saved bitrate is available. Camera-settings mode is intended for planning when that information is unknown.

Example: One Hour of Video at 100 Mbps

Suppose:

1. Combine Video and Audio Bitrates

Convert audio to Mbps:

256 kbps ÷ 1,000 = 0.256 Mbps

Combined media bitrate:

100 + 0.256 = 100.256 Mbps

2. Convert Bitrate Into Stored Bytes

One hour contains:

3,600 seconds

Encoded media payload:

100.256 × 1,000,000 × 3,600 ÷ 8

= 45,115,200,000 bytes

Using decimal storage units:

= 45.1152 GB

3. Apply File Overhead

At 1%:

45,115,200,000 × 0.01 = 451,152,000 bytes

Completed clip size:

45,115,200,000 + 451,152,000

= 45,566,352,000 bytes

Estimated file size:

• 45.57 GB
• approximately 42.44 GiB

The completed results are:

This estimate assumes that 100 Mbps reasonably represents the average video bitrate of the saved recording.

Calculate Storage From a Known Bitrate

Known-bitrate mode uses:

Completed clip bytes = [(Video Mbps + Audio kbps ÷ 1,000) × 1,000,000 × Duration seconds ÷ 8] × (1 + Overhead % ÷ 100)

When audio is disabled:

Audio bitrate = 0

A useful known bitrate can come from:

• a measured finished recording;
• a configured CBR bitrate;
• a configured ABR target;
• manufacturer documentation;
• recorder or camera statistics.

For variable-bitrate recordings, a representative average is generally more useful for storage planning than a maximum or short-term peak.

Actual average bitrate can vary with:

• scene complexity;
• movement;
• image noise;
• encoder behavior;
• frame structure;
• camera processing.

Do not assume that a published maximum bitrate is sustained throughout the recording unless the recording mode is designed to behave that way.

Do Not Apply Camera-Setting Factors to a Known Bitrate

Once the complete saved video bitrate is known, do not multiply it again by:

• resolution;
• frame rate;
• codec;
• bit depth;
• chroma subsampling.

Those characteristics influence how the recorder produces its bitrate. They do not need to be applied a second time after a representative saved bitrate is already known.

Audio remains separate because it has its own bitrate input.

Use the Correct Bitrate Unit

Known-bitrate mode accepts:

• Mbps;
• Gbps;
• MB/s.

Important conversions are:

1 Gbps = 1,000 Mbps

and:

1 MB/s = 8 Mbps

For example:

25 MB/s × 8 = 200 Mbps

If a camera reports:

25 MB/s

but the value is entered as:

25 Mbps

the storage estimate will be too low by a factor of eight.

Remember:

• lowercase b = bits;
• uppercase B = bytes.

Estimate Bitrate From Camera Settings

When no reliable recorded bitrate is available, camera-settings mode estimates one from:

• recording resolution;
• frame rate;
• recording profile;
• optional planning range for compressed profiles.

The reference point is:

1920 × 1080 at 30 fps

Built-in reference rates are:

For compressed profiles:

Estimated bitrate = Profile reference × Pixel factor × Frame-rate factor × Planning-range factor

For the calculator’s uncompressed 10-bit 4:2:2 reference:

Estimated bitrate = Uncompressed reference × Pixel factor × Frame-rate factor

These are transparent calculator planning references, not guarantees for every camera or recorder using the same profile name.

Actual bitrate can depend on the implementation, source material, encoder, recording mode, and camera settings.

The ProRes values in the table align closely with Apple’s published approximate target data rates for 1920 × 1080 at 29.97 fps. See Apple’s official About Apple ProRes documentation for the underlying format guidance.

Calculate the Resolution Factor

Camera-settings mode adjusts the 1080p reference according to pixel count:

Pixel factor = (Selected width × Selected height) ÷ (1920 × 1080)

Examples:

For 3840 × 2160:

8,294,400 ÷ 2,073,600 = 4

So the calculator applies a:

4× pixel factor

before other relevant factors.

Names such as 4K, 5.7K, 6K, and 8K can refer to different exact dimensions on different cameras.

Use custom width and height when the actual recorded dimensions are known.

The pixel factor is part of the calculator’s estimation model. A real camera does not necessarily increase bitrate in exact proportion to pixel count.

Calculate the Frame-Rate Factor

The calculator uses a 30 fps reference:

Frame-rate factor = Selected fps ÷ 30

For example:

60 ÷ 30 = 2

so 60 fps applies a:

2× frame-rate factor

to the reference bitrate.

This is a planning relationship. A real camera’s 60 fps mode does not necessarily record at exactly twice the average bitrate of its 30 fps mode.

Apply the Planning Range to Compressed Profiles

Compressed camera-setting estimates can use:

This multiplier represents uncertainty around the selected profile reference.

It is not:

• a camera quality setting;
• a manufacturer bitrate mode;
• an encoder preset.

The planning multiplier is not applied to the uncompressed 10-bit 4:2:2 reference.

Interpret Recording Profiles by Bitrate

Different codec and recording-profile names can suggest different typical bitrate ranges, but storage ultimately follows the bitrate actually written.

A more efficient codec can sometimes provide comparable visual quality at a lower bitrate.

However:

same average bitrate × same duration = same media payload

So if an H.264 recording and an H.265 recording both average:

100 Mbps

for the same duration, their mathematical video payloads are the same size.

The calculator does not assume a fixed storage reduction simply because H.265 is selected.

Understand the Uncompressed 10-Bit 4:2:2 Reference

The calculator’s uncompressed reference is approximately:

1,244 Mbps at 1920 × 1080 and 30 fps

The simplified model assumes approximately:

20 stored bits per pixel

for the active raster.

So:

1920 × 1080 × 30 × 20

= 1,244,160,000 bits/second

or approximately:

1,244 Mbps

This simplified reference does not include every possible storage implementation detail, such as:

• row padding;
• frame alignment;
• ancillary data;
• block padding;
• recorder-specific packing.

Actual uncompressed recording rates can therefore differ.

Add the Audio That Is Actually Saved

Enter the combined encoded bitrate of all audio streams stored in the recording.

Suppose:

• program audio: 256 kbps
• commentary track: 128 kbps

Combined audio bitrate:

256 + 128 = 384 kbps

Enter:

384 kbps

If a stereo stream is documented as:

256 kbps total

enter 256 kbps.

Do not multiply it by two merely because it contains two channels unless the specification explicitly gives a per-channel bitrate.

For audio-only file sizing or more detailed audio calculations, use the Audio File Size Calculator.

Apply File Overhead

Recorded files can contain data beyond encoded picture and sound.

The optional overhead allowance can approximate scalable structures such as:

• indexes;
• timestamps;
• track information;
• codec headers;
• camera metadata;
• container structures.

Use:

Completed storage = Encoded payload × (1 + Overhead % ÷ 100)

At 1%:

Completed storage = Payload × 1.01

The percentage is an editable planning allowance rather than a universal value for every MP4, MOV, MXF, or other container.

Very short clips can behave differently because some file structures include fixed per-file data that does not scale proportionally with duration.

For that reason, percentage-based overhead is best treated as a practical estimate rather than an exact container parser.

Calculate Multiple Identical Clips

When several clips use identical settings:

Total storage = Completed clip size × Number of clips

Using the one-hour example:

45.566352 GB × 10

= 455.66352 GB

Approximately:

• 455.66 GB
• 424.37 GiB

This multiplication assumes the clips share the same:

• duration;
• video bitrate;
• audio bitrate;
• overhead allowance.

If recordings differ substantially, calculate them as separate groups and add their storage totals.

For example:

• 10 clips at 100 Mbps;
• 5 clips at 400 Mbps;
• 3 clips with no audio

are clearer as three calculations than as one artificial average.

Compare Recording Storage With a Card or Drive

Capacity comparison can estimate:

• usable capacity after a free-space reserve;
• maximum recording duration;
• complete selected-duration clips that fit;
• percentage of usable capacity required.

Supported units include:

• GB;
• TB;
• GiB;
• TiB.

Use:

Usable capacity = Entered capacity × (1 − Reserved % ÷ 100)

The calculator uses the capacity value supplied to it. It does not inspect a physical drive or memory card.

If existing files, hidden partitions, device databases, or other reserved areas reduce available recording space, account for them in the entered capacity or reserve.

Example: 128 GB Card With 5% Reserved

Using the opening one-hour recording:

Entered capacity:

128 GB

Reserve:

5%

Usable capacity:

128 × 0.95 = 121.60 GB

One hour requires:

45.566352 GB

Maximum Recording Time

121.60 ÷ 45.566352 ≈ 2.67 hours

Approximately:

2 hr 40 min

Complete One-Hour Clips

Floor(121.60 ÷ 45.566352)

= 2 clips

Capacity Used by One Clip

45.566352 ÷ 121.60 × 100

≈ 37.47%

One planned one-hour recording therefore consumes approximately:

37.47%

of the post-reserve capacity.

Understand GB and GiB

Decimal storage uses:

1 GB = 1,000,000,000 bytes

Binary storage uses:

1 GiB = 1,073,741,824 bytes

The opening example contains:

45,566,352,000 bytes

which can be displayed as approximately:

• 45.57 GB
• 42.44 GiB

The underlying byte count is identical.

Use the same unit system when comparing the calculated result with the stated capacity of a card, SSD, or drive.

Scale a Known Recording Rate

Once the completed storage rate is known, the calculator can report normalized values such as storage per minute and per hour.

For the opening example:

• ≈ 759.44 MB/min
• ≈ 45.57 GB/hr

At the same average bitrate and overhead:

2 hours ≈ 91.13 GB

and:

30 minutes ≈ 22.78 GB

These quick projections remain subject to the same bitrate and overhead assumptions as the original calculation.

Use a Screen-Specific Model for Screen Capture

Screen recordings can behave differently from camera footage because a desktop image may alternate between:

• static interfaces;
• text;
• scrolling;
• animation;
• full-motion video.

For screen-capture planning, use the Screen Recording File Size Calculator.

The core bitrate × duration relationship is the same, but the planning assumptions are tailored to screen recording.

Use CCTV Storage for Multi-Camera Retention

Ordinary video file sizing does not directly model:

• many cameras;
• recording schedules;
• motion-recording percentages;
• long retention periods;
• per-camera archival assumptions;
• NVR capacity planning.

For those calculations, use the CCTV Storage Calculator.

Software Input Limits

These are calculator validation limits, not recommended recording settings or equipment specifications.

Calculation Boundaries

The Video Recording Storage Calculator estimates file size from the inputs supplied.

It does not:

• inspect an actual media file;
• determine visual quality;
• verify camera compatibility;
• calculate required card write speed;
• model editing proxies or cache storage;
• inspect remaining space on a physical device;
• reproduce every manufacturer recording mode;
• infer an exact sensor data rate from a generic profile name.

Long recordings may also be split into multiple files by a camera, recorder, or file system. Segmentation normally preserves a similar media payload but can introduce additional per-file structures.

Calculation Method

Known-Bitrate Mode

Combined bitrate:

Combined bitrate = Video bitrate + Audio bitrate

Encoded payload:

Encoded payload bytes = Combined bitrate × Duration seconds ÷ 8

Completed clip size:

Completed clip size = Encoded payload × (1 + Overhead % ÷ 100)

Camera-Settings Mode

For compressed profiles:

Estimated bitrate = Profile reference × Pixel factor × Frame-rate factor × Planning factor

For the calculator’s uncompressed reference:

Estimated bitrate = Uncompressed reference × Pixel factor × Frame-rate factor

Multiple Clips

Total storage = Completed clip size × Clip count

Capacity Comparison

Usable capacity = Entered capacity × (1 − Reserved % ÷ 100)

Maximum recording duration = Usable capacity ÷ Completed storage rate

Complete clips supported = Floor(Usable capacity ÷ Completed clip size)

The calculator performs these calculations using the underlying unrounded values. Display precision changes only how the resulting values are shown.