IOPS Calculator
The IOPS Calculator works out the theoretical input/output performance of your storage from its latency and queue characteristics. Enter Average Latency in milliseconds, Queue Depth, and Block Size, then click Calculate IOPS to see theoretical IOPS, throughput in MB/s, and effective bandwidth — the numbers that tell you whether your storage can handle your database, virtual machines, or transaction workload.
Drive Count, Block Size and Read/Write Mix Parameters
Total IOPS, Throughput (MB/s) and Effective Latency
Theoretical IOPS
Throughput
Read IOPS
Write IOPS
Formula:
IOPS = (1000 / Latency_ms) × Queue_Depth
Throughput_MB/s = (IOPS × Block_Size_KB) / 1024
How Block Size Affects IOPS, MB/s and Storage Latency
| Block Size | IOPS | Throughput | Typical Use |
|---|---|---|---|
| 4 KB | — | — | Databases, random I/O |
| 8 KB | — | — | SQL Server, Oracle |
| 64 KB | — | — | File servers, mixed workloads |
| 256 KB | — | — | Streaming, sequential I/O |
| 1 MB | — | — | Video editing, large files |
SSD vs HDD vs NVMe: IOPS and MB/s Benchmarks by Drive Type
| Storage Type | Typical Latency | 4K Random IOPS | Sequential MB/s |
|---|---|---|---|
| 7200 RPM HDD | 8-12 ms | 75-150 | 100-200 |
| 10K RPM HDD | 5-8 ms | 150-250 | 150-250 |
| 15K RPM HDD | 3-5 ms | 200-350 | 200-300 |
| SATA SSD | 0.1-0.5 ms | 50K-100K | 400-550 |
| NVMe SSD | 0.02-0.1 ms | 100K-1M+ | 3,000-7,000 |
| Intel Optane | 0.01 ms | 500K-2M+ | 2,500-3,000 |
What Is IOPS? Input/Output Operations Per Second Explained
IOPS (Input/Output Operations Per Second) is the primary metric for measuring storage performance in random access workloads. Understanding IOPS helps you size storage systems correctly for databases, virtual machines, and transaction-heavy applications. The relationship between IOPS, latency, and queue depth follows predictable formulas that this calculator implements. Learn more: convert between storage units.
Block size significantly impacts both IOPS and throughput measurements. Small block sizes (4KB-8KB) are typical for database workloads and result in higher IOPS but lower throughput. Large block sizes (64KB-1MB) are common for sequential operations like video streaming, yielding lower IOPS but much higher throughput in MB/s. Related: Bandwidth and throughput converter.
Modern NVMe SSDs can deliver hundreds of thousands of IOPS at sub-millisecond latencies, far exceeding traditional spinning disks. When planning storage infrastructure, consider both current requirements and future growth. A system that performs well at 50% utilization may struggle as workloads increase and queue depths grow. See also: StorageMath calculators.
Queue Depth, Cache Hits and Storage Latency Defined
IOPS (Input/Output Operations Per Second): Measures the number of read/write operations a storage system can perform per second.
Latency: The time delay between requesting data and receiving it. Lower is better.
Queue Depth: Number of outstanding I/O requests. Higher queue depth can increase IOPS but may also increase latency.
Block Size: The size of each I/O operation. Smaller blocks = more IOPS but less throughput. Larger blocks = fewer IOPS but more throughput.