What this calculator works out
This calculator multiplies photo count by average file size and the number of copies you keep, giving the total storage in gigabytes.
The copies figure is the one people leave at one. A single copy is not a backup, and photographs are the household data that cannot be recreated.
Enter your details
Before you plan storage
- Average file size varies enormously. A JPEG from a phone might be 3 to 8 MB; a RAW file from a full-frame camera 25 to 60 MB.
- Count the copies you actually want: the working copy, a local backup and an off-site or cloud copy is three.
- Shooting RAW plus JPEG roughly doubles the per-photo figure.
- Edited versions, exports and panorama stacks all add to the total beyond the original captures.
The widely used backup rule: three copies of the data, on at least two different types of media, with one copy kept somewhere else. It exists because the common failure modes — drive failure, accidental deletion, theft, fire and ransomware — are each defeated by a different part of it. A second drive in the same room addresses only the first.
How this calculator works
Photos times size times copies:
Gigabytes = photos × average file size in MB × copies ÷ 1,024Dividing by 1,024 uses binary gigabytes, which is how operating systems report capacity. Drive manufacturers use decimal gigabytes of 1,000 MB, which is why a drive sold as 1 TB shows as roughly 931 GB.
Worked example: 2,000 RAW files
Using the default figures — 2,000 photos averaging 25 MB, kept in 2 copies:
- Total storage: 97.66 GB
Under 100 GB, which sounds modest. But 2,000 photos is a single active year for many photographers, and two copies is one short of the usual rule. At three copies and ten years the same shooting rate needs about 1.5 TB — and the growth is the point, because storage bought for this year's photographs will be full within two.
Common mistakes
- Counting one copy. A single copy is storage, not backup.
- Keeping both copies in the same place. Fire, theft and flood take both.
- Using a phone JPEG size for RAW files. They differ by a factor of five or more.
- Forgetting edits and exports. They can equal the originals in volume.
- Sizing for today. Photograph libraries only grow.
Frequently asked questions
How should I back up photographs?
Three copies, two media types, one off-site. In practice: the working library on a computer, a local backup on an external drive or NAS, and a cloud copy. Cloud sync alone is not a backup — a deletion or corruption propagates to the cloud copy, which is why versioned backup matters more than sync.
Should I shoot RAW or JPEG?
RAW preserves the sensor data and gives far more latitude in editing, at several times the file size and requiring processing. JPEG is finished, small and immediately usable. Many photographers shoot RAW for anything they care about and JPEG for volume work. Storage cost has fallen enough that file size is rarely the deciding factor now.
How long do storage media last?
Hard drives commonly fail between three and five years, though the distribution is wide and failure is often sudden. SSDs fail differently and can lose data if left unpowered for very long periods. Optical media degrade. No medium is archival in a household setting, which is why the answer is multiple copies and periodic migration rather than a durable disc.
Is cloud storage enough on its own?
It covers the off-site requirement well and the versioning requirement variably. It does not cover the provider closing, an account being locked, or a subscription lapsing. For irreplaceable photographs, a local copy alongside the cloud copy is the sensible arrangement, which is exactly what the three-copy rule describes.
Is what I enter stored?
No. Figures are processed in your browser and never transmitted or retained.
Related tools
References
- GOV.UK — data protection and guidance on storing personal information
- Information Commissioner's Office — handling and storing personal data, including photographs of people
Sources are checked at publication and can change — how I choose and check references.