When choosing between CrystalDiskMark and CrystalDiskInfo , the primary difference lies in their purpose: CrystalDiskMark measures how fast your drive is (performance), while CrystalDiskInfo tells you if your drive is dying (health) . Both tools are developed by the same Japanese developer, Noriyuki Miyazaki (hiyohiyo), and are open-source, industry-standard utilities for Windows. CrystalDiskMark: The Speedometer CrystalDiskMark is a benchmarking tool designed to measure the sequential and random read/write speeds of storage devices like SSDs, HDDs, and USB flash drives. Is crystaldiskinfo and crystaldiskmark safe? : r/techsupport
Technical Report: Comparative Analysis of CrystalDiskMark and CrystalDiskInfo 1. Executive Summary While both utilities are developed by the same author (hiyohiyo) and share a similar name, CrystalDiskMark and CrystalDiskInfo serve entirely different purposes. One is a benchmarking tool (performance), and the other is a diagnostic tool (health). They are complementary, not competitive. 2. Core Purpose & Functionality | Feature | CrystalDiskMark | CrystalDiskInfo | | :--- | :--- | :--- | | Primary Goal | Measure read/write speed | Assess drive health & reliability | | Key Metrics | Sequential & random IOPS, MB/s | S.M.A.R.T. attributes, temperature, uptime | | Output | Numerical scores & throughput graphs | Health status (Good/Caution/Bad), raw attribute values | | Use Case | Performance testing, benchmarking, troubleshooting slowness | Predicting drive failure, checking error rates, monitoring wear | 3. Detailed Technical Comparison 3.1 CrystalDiskMark (Performance Benchmark)
How it works: Writes temporary test files (e.g., 1 GiB) to the drive and measures the time taken to read/write under different conditions. Key tests:
SEQ1M Q8T1: Sequential 1 MiB blocks, Queue Depth 8, Thread 1 (high throughput, large files). SEQ1M Q1T1: Sequential 1 MiB blocks, QD1 (realistic large file copy). RND4K Q32T16: Random 4 KiB blocks, QD32, Threads 16 (high queue depth for server workloads). RND4K Q1T1: Random 4 KiB, QD1 (most typical for OS & application usage – low queue depth random I/O). crystaldiskmark vs crystaldiskinfo
Output interpretation: Higher MB/s and IOPS are better. Useful for comparing against manufacturer specs or verifying performance after driver/firmware changes.
3.2 CrystalDiskInfo (Health Monitor)
How it works: Reads S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) data directly from the drive firmware. Key attributes monitored: Is crystaldiskinfo and crystaldiskmark safe
Reallocated Sectors Count: Bad sectors remapped to spare area. High = failing media. Current Pending Sector Count: Unstable sectors awaiting remap. Uncorrectable Sector Count: Physically damaged sectors with data loss. SSD Wear Leveling Count / Total LBAs Written: Remaining lifespan of NAND flash. Power-On Hours / Power Cycle Count: Usage age.
Output interpretation:
Blue / Good: S.M.A.R.T. values within safe limits. Yellow / Caution: One or more attributes near threshold (backup immediately). Red / Bad: Threshold exceeded – drive failure imminent or already occurring. One is a benchmarking tool (performance), and the
4. When to Use Which Tool | Scenario | Recommended Tool | | :--- | :--- | | My computer feels slow. Is the SSD underperforming? | CrystalDiskMark (run benchmark, compare to expected speeds) | | My PC randomly freezes or crashes. Is the drive dying? | CrystalDiskInfo (check S.M.A.R.T. and pending sectors) | | I just installed a new NVMe drive. Is it running at PCIe 4.0 speed? | CrystalDiskMark (verify sequential speeds) | | The drive shows 100% usage in Task Manager but low throughput. | CrystalDiskInfo (look for high error rates or reallocations) | | I want to see total data written to my SSD over its life. | CrystalDiskInfo (read "Total Host Writes" attribute) | 5. Limitations CrystalDiskMark
Does not detect failing hardware. A drive can show excellent benchmark results but still be corrupting data due to bad sectors. Short test may not reveal thermal throttling (requires extended runs). Cache effects: Many modern SSDs have fast pseudo-SLC caches; CDM may show inflated results that don't reflect sustained real-world performance.