Storage Duration
Calculator

Inputs

Recording minutes
170.666666

Results

Recording minutes
170.666666

Media and photography results

Recording minutes170.666666

formula-map diagram

Recording minutes
170.666666

Media and photography relationship

Formula

minutes = capacity × 8 ÷ bitrate

= 170.66666666667

Note

This result uses the values you entered and a simplified planning equation; verify quantities and local requirements before purchasing or building.

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Frequently asked questions

How is recording duration calculated from storage capacity and bitrate?+

Duration in seconds equals available storage (converted to bits) divided by bitrate (in bits per second), the inverse of the file-size calculation. A 128 GB card at a 50 Mbps recording bitrate yields roughly 5.7 hours of footage.

Why does the same memory card record different durations depending on the quality setting?+

Higher quality settings (higher resolution, frame rate, or bitrate) use more data per second of footage, so the same fixed storage capacity is consumed faster at a 4K/100Mbps setting than at a 1080p/25Mbps setting, resulting in much shorter total recording time at higher quality.

Why does the actual usable storage capacity always come in slightly less than the advertised number?+

Storage manufacturers calculate capacity using decimal units (1 GB = 1,000,000,000 bytes), while operating systems and cameras often display capacity in binary units (1 GB = 1,073,741,824 bytes), and the device's file system and firmware also reserve some space for its own use, so a '128GB' card typically shows closer to 119GB of actually usable space.

How is this useful for planning a long shoot, like a full-day event or a security camera setup?+

Calculating storage duration in advance tells you exactly how many cards to bring, how often you'll need to swap or offload media during a shoot, or how large a drive a continuously-recording security system needs to cover a target retention period (like 30 days) before old footage gets overwritten.

Does variable bitrate (VBR) recording make this calculation less reliable?+

Yes, VBR footage fluctuates its bitrate based on scene complexity, so the calculator's output for VBR should be treated as an estimate based on the average or typical bitrate, rather than an exact guarantee, since a scene with lots of motion or detail will consume storage faster than a static, simple scene at the same nominal setting.