IIoT, SCADA & Edge Connectivity calculator

Data Historian Storage Cost Calculator

Estimate annual historian storage cost. Enter the total tags being written, the storage cost per tag-year (disk plus replication plus backup), the compression and retention efficiency (how much disk is recovered through swinging-door, deadband, and rollups), and a fixed historian server and license adder. The calculator returns variable storage spend and the loaded total.

What this calculator does

  • Estimate annual on-prem historian storage cost from total tags written, the storage cost per tag-year (covering disk, replication, and backup), the storage compression and retention efficiency, and a fixed historian server and license adder.
  • Use it when a historian admin or plant IT lead is sizing storage for an OSIsoft PI, AVEVA Historian, Inductive Tag Historian, or InfluxDB OT deployment before the next budget cycle.
  • It returns the annual on-prem historian storage cost, broken into variable per-tag spend and a fixed server and license line.

Formula used

  • Variable historian storage cost = tags written × storage cost per tag-year × compression and retention efficiency
  • Total historian storage cost = variable storage cost + fixed historian server and license cost

Inputs explained

  • Tags written to historian: Use the count of unique tags written to the historian (active points, not historical tags from retired equipment).
  • Storage cost per tag-year: Use disk plus replication plus backup cost per tag-year (often 0.05 to 0.50 dollars per tag-year for on-prem; higher for cloud-hosted).
  • Compression and retention efficiency: Use the share of raw disk recovered through swinging-door compression, deadband, and rollups (typical 60 to 90 percent for PI; 40 to 70 percent for time-series databases like InfluxDB without aggressive aggregation).
  • Fixed historian server and license cost: Include historian server hardware, OS, historian license seats, DR or hot-standby, and admin labor amortized over the year.

How to use the result

  • Run it before the next budget cycle, when sizing storage for a tag count expansion, or when comparing on-prem historian against a cloud historian.
  • It is a storage cost view. Use the cloud historian cost calculator for cloud-hosted compare, the data loss exposure calculator for outage exposure, and the OT data completeness calculator for tag quality.

Common questions

  • How do I get cost per tag-year? Take total annual storage spend on the historian (disk array share, replication, backup, snapshot) and divide by tag count. On-prem typically lands at 0.05 to 0.50 dollars per tag-year.
  • What compression efficiency should I assume for PI Server? PI Server with default swinging-door and exception thresholds usually retrieves 60 to 90 percent of raw disk volume. Tighter exception or aggressive deadbands can push higher; ask your PI admin for the actual ratio.
  • How do I model retention tiers? Run the calculator twice: once for hot tier (1 year of full-resolution tags) and once for cold tier (rollups or compressed cold storage). Use a different cost-per-tag-year for each tier.
  • Should I include the cost of the historian dashboards? No. Dashboard runtime is separate. Use the SCADA screen utilization calculator for HMI dashboards and a separate ticket for analytics tools (PI Vision, AVEVA Insight).

Last reviewed 2026-05-12.