Data Loss Risk Calculator

RPO (Recovery Point Objective) is the maximum acceptable amount of data loss measured in time: it defines the age of the most recent backup from which recovery must be possible. If RPO is 4 hours, the organization accepts losing up to 4 hours of data. Maximum potential data loss = data_change_rate_per_hour * RPO_hours. Backups must run at least as frequently as the RPO.

Data at risk = data_change_rate * time_since_last_backup. For a database generating 10 GB of changes per hour with a 4-hour backup interval, maximum data at risk is 40 GB per failure event. This is the data that would need to be re-entered or reconstructed if a failure occurs just before the next backup.

Data loss risk describes the probability and volume of data that could be permanently lost. Backup gap is the time between when a backup runs and the next scheduled backup - during this window, any new data is unprotected. The backup gap equals the backup interval for simple periodic backups. Continuous replication reduces the gap to near zero.

Synchronous replication writes data to a secondary site before acknowledging the write to the application, giving zero data loss (RPO = 0) but adding write latency. Asynchronous replication copies data to the secondary site after acknowledgment, giving near-zero to small RPO depending on replication lag, with no impact on primary site write latency. Log shipping copies database transaction logs on a schedule, similar to periodic backups.

Business cost of data loss = (volume of lost records) * (average value per record). For transactional systems: lost transactions * average transaction value. For customer records: records at risk * GDPR fine per record (up to EUR 20/record for systematic failures) + reputational and re-entry costs. The total cost often exceeds the investment in continuous backup solutions by orders of magnitude.