Estimate your backup storage needs in seconds. Enter your data sources, configure your strategy, and get accurate projections for storage, bandwidth, and growth.
Enter the size of each data type in GB
Configure your backup strategy
42 GB
Raw Data
Before compression
27.3 GB
Compressed
medium compression
66.9 GB
Total Storage
30 backups retained
73.6 GB
12-Month Forecast
+10% growth
830.4 GB
Monthly Transfer
Daily backups
Keep 3 copies, on 2 different media types, with 1 offsite. This ensures recovery from any disaster scenario.
Regularly test your backup restores. A backup you can't restore from is worthless — verify monthly at minimum.
Use incremental backups after the initial full backup to save storage and bandwidth. Only changed data is copied.
Planning a reliable backup strategy starts with knowing exactly how much storage you need. Without accurate calculations, you risk either overpaying for unused storage or running out of space when you need it most. Our free Backup Size Calculator helps IT professionals, system administrators, and business owners estimate their backup storage requirements with precision — factoring in compression ratios, retention policies, and data growth projections.
Simply enter the size of your data across five categories — documents, photos, videos, databases, and emails. Then configure your backup strategy including compression level, backup frequency, retention period, and expected annual growth rate. The calculator instantly computes your raw data size, compressed backup size, total storage needed with retention, a 12-month growth forecast, and monthly bandwidth requirements.
Backup compression reduces the size of your data before storing it, saving both storage space and transfer bandwidth. Text-heavy files like documents and emails compress extremely well (up to 55% reduction), while already-compressed formats like JPEG images and MP4 videos see minimal benefit. Our calculator offers four compression levels — none, low (15%), medium (35%), and high (55%) — to match your specific data mix and backup software capabilities.
Retention period determines how long you keep backup copies before they are overwritten or deleted. Longer retention means more storage but better protection against data corruption that goes unnoticed for days or weeks. Most organizations follow a tiered approach: daily backups retained for 30 days, weekly backups for 3 months, and monthly backups for 1 year. Regulatory requirements in industries like healthcare (HIPAA) and finance (SOX) may mandate specific retention periods.
The industry-standard 3-2-1 backup rule recommends keeping 3 copies of your data, stored on 2 different media types, with 1 copy offsite. This strategy protects against hardware failure, ransomware, natural disasters, and human error simultaneously. When using this calculator, consider that your total storage needs may triple if you follow the 3-2-1 rule across local NAS, external drives, and cloud storage providers like AWS S3, Google Cloud Storage, or Azure Blob Storage.
Our calculator uses an incremental backup model where only the first backup is a full copy, and subsequent backups capture only changed data (approximately 5% per cycle). This dramatically reduces storage compared to running full backups every time. Modern backup solutions like Veeam, Acronis, Duplicati, and Restic all support incremental backups with deduplication, making your actual storage needs even lower than our conservative estimates.
Our calculator provides conservative estimates based on industry-standard compression ratios and incremental backup models. Actual results may vary depending on your specific data types, backup software, and deduplication capabilities.
Ideally both. Cloud storage offers offsite protection and scalability, while local backups provide faster restore times. Use the monthly bandwidth estimate to plan your cloud upload requirements and internet connection needs.
Test restore procedures at least monthly for critical systems and quarterly for general data. Untested backups are unreliable — many organizations discover corruption only when they need to restore, which is too late.