Why Check Drive Health?

Hard drives (HDDs) and SSDs fail without warning — or with subtle warning signs readable by software. S.M.A.R.T. (Self-Monitoring, Analysis and Reporting Technology) is built into all modern drives and tracks hundreds of reliability indicators. Checking S.M.A.R.T. data can warn you of impending failure before you lose data.

Check on Windows — CrystalDiskInfo (Free)

  1. 1

    Download CrystalDiskInfo from crystalmark.info

    CrystalDiskInfo is a free, reputable tool. Download and install it. Open it — it reads your drive’s S.M.A.R.T. data immediately.

  2. 2

    Read the health status

    Each drive shows a coloured health status: Good (blue): drive is healthy, all S.M.A.R.T. values within normal range. Caution (yellow): one or more values indicate potential issues — back up immediately and monitor closely. Bad (red): drive failure is imminent or occurring — back up immediately and replace the drive. Also note the temperature — HDDs should be under 50°C, SSDs under 70°C under load.

  3. 3

    Key S.M.A.R.T. values to watch

    Reallocated Sectors Count (ID 05): sectors the drive has remapped due to errors. Any value above 0 on an HDD is concerning. Pending Sectors (C5): sectors waiting to be reallocated — sign of physical damage. Uncorrectable Sector Count (C6): sectors that could not be corrected — serious. Power-On Hours: total hours the drive has been running — context for age.

Check on Mac

  1. 4

    Disk Utility → First Aid (basic check)

    Applications → Utilities → Disk Utility. Select your drive. Click First Aid → Run. This checks the file system for errors but not full S.M.A.R.T. data. The sidebar shows a small S.M.A.R.T. status (Verified = good, Failing = bad).

  2. 5

    DriveDx for detailed S.M.A.R.T. data (paid, $20)

    DriveDx provides detailed S.M.A.R.T. data for Mac similar to CrystalDiskInfo on Windows. Worth the investment if you are concerned about drive health or have an ageing Mac.

If your drive shows Caution or BadBack up immediately to an external drive or cloud storage before doing anything else. Do not shut down the computer until the backup is complete if possible — a failing drive may not be readable on the next boot. Replace the drive as soon as practical.

Frequently Asked Questions

Traditional HDDs typically last 3–5 years with normal use, though many last much longer. SSDs generally last longer than HDDs and are more resistant to physical shock. Manufacturer warranty periods (typically 3–5 years) are a rough indicator of expected lifespan. Age, heat, heavy usage and physical shocks all reduce lifespan. Regular S.M.A.R.T. checks from year 3 onward are good practice.
Yes — CrystalDiskInfo reads S.M.A.R.T. data from both HDDs and SSDs. For SSDs, the relevant indicators differ slightly: Total Bytes Written (TBW) tracks how much data has been written to the SSD over its lifetime, and Wear Levelling Count tracks the overall wear of the flash memory cells. NVMe SSDs are also supported in recent versions of CrystalDiskInfo.