Database Sizing Calculator

Estimate database storage, IOPS, and RAM requirements from row count and query patterns.

Total row count

Avg row size (bytes)

Number of indexes

Index size % of data

Reads per second

Writes per second

Monthly growth rate %

Replication factor

Tab to move between fields

Total storage needed (GB)

12.4

Required IOPS

1,450

Recommended RAM (GB)

Raw data size (GB)2.38

Index overhead (GB)3.58

Single instance storage (GB)6.2

Connection pool size67

Storage in 12 months (GB)22.26

How to Use This Calculator

Enter the Total Row Count and Average Row Size (bytes) for your primary table.
Input the number of Indexes and their Index Size % of data overhead.
Set Reads per Second and Writes per Second from your application metrics.
Enter Monthly Growth Rate % and Replication Factor.
Review Total Storage Needed (GB) and Total IOPS to select the right database instance size.

How the result changes with Total row count

Total row count	Total storage needed (GB)	Required IOPS	Recommended RAM (GB)
100,000,000,000	123,977.66	1,450	44,585
350,000,000,000	433,921.81	1,450	156,045
650,000,000,000	805,854.8	1,450	289,798
900,000,000,000	1,115,798.95	1,450	401,259

Total row count: Total number of rows across primary tables.
Avg row size (bytes): Average size of a single row including all columns (typically 100-1000 bytes).
Number of indexes: Total secondary indexes across tables.
Index size % of data: Each index adds this percentage of the data size (B-tree ~20-40%).
Reads per second: Average read queries per second hitting the database.
Writes per second: Average INSERT/UPDATE/DELETE operations per second.
Monthly growth rate %: Expected monthly data growth rate.
Replication factor: Number of data copies (1 = no replication, 2 = primary + 1 replica).

Total storage needed (GB): Total disk space including data, indexes, WAL, and replication.
Required IOPS: Estimated IOPS needed to handle read + write load.
Recommended RAM (GB): RAM needed to keep working set and indexes in memory.
Raw data size (GB): Data size before indexes and overhead.
Index overhead (GB): Space consumed by all secondary indexes.
Single instance storage (GB): Total per-instance storage (data + indexes + WAL).
Connection pool size: Recommended database connection pool size.
Storage in 12 months (GB): Projected total storage after 12 months of growth.

Identify Input Parameters
4 parameters
Total row count = 10000000, Avg row size (bytes) = 256, Number of indexes = 5, Index size % of data = 30 = 8 input(s) provided
Calculate Total storage needed
Total storage needed = singleInstanceGB * replicationFactor
12.4 = 12.4
Calculate Required IOPS
Required IOPS = readIOPS + writeIOPS
1450 = 1450
Calculate Recommended RAM
Recommended RAM = max(1
5 = 5
Calculate Raw data size
Raw data size = (rowCount * avgRowSizeBytes) / (1024 * 1024 * 1024)
2.38 = 2.38
Calculate Index overhead
Index overhead = rawDataGB * (indexCount * (indexOverheadPct / 100))
3.58 = 3.58