An SSD hides two entirely separate dangers. The first is a slow one you can watch coming — flash wear — and every health tool on the market reports it plainly. The second is a switch that gives no notice at all: the controller, silent right up to the moment it stops. Checking an SSD properly means reading the slow gauge and never forgetting the silent switch behind it.
The health percentage tracks flash wear faithfully — and tells you nothing about the controller or firmware faults that actually end most SSDs. Read it for what it is; don’t mistake it for a promise of tomorrow.
On Windows, one download settles it: CrystalDiskInfo lists every SATA and NVMe drive with its health percentage, temperature and the full attribute table underneath. If your SSD is a Samsung, Crucial or WD, their own utilities — Magician, Storage Executive, the WD Dashboard — add lifetime-write totals and firmware updates in language you don’t need a manual to parse. On a Mac, Disk Utility hands you the one-word SMART verdict, and smartctl (part of smartmontools, a quick Homebrew install) hands you the rest — Apple silicon’s built-in storage included.
Wherever you’re reading, four figures do the real work. Percentage Used is the official NVMe wear meter, ticking up from zero — or you’ll see its cheerier mirror image, the ‘health’ score. Total bytes written only means anything next to the drive’s TBW rating from its spec sheet; the great majority of SSDs are retired with most of that budget still untouched. Available Spare is the reserve of replacement blocks the controller draws on as flash wears out — it wants to be at or near 100%, and a visible drop is the plainest wear warning you’ll get. Media and Data Integrity Errors has exactly one acceptable reading — zero — no matter how healthy the headline number looks.
Now the awkward truth every recovery bench can confirm: the SSDs that turn up dead are hardly ever worn out. They turn up with immaculate wear figures and a controller that simply stopped replying — a firmware crash or an electronics fault that carries the drive from flawless to gone between two boots. The part that failed is the very part that writes the health report, which is why not a single gauge saw it coming. File that as a design fact rather than misfortune: an SSD’s health check measures wear, and a backup is the only thing that covers you for the switch.
The consolation sits behind the failure. A dead controller usually leaves the NAND flash — and your files — physically whole, sealed inside a drive that refuses to talk. Firmware-level repair and reading the chips directly exist precisely for this, rebuilding data the controller can no longer hand over: it’s the heart of our SSD not detected work, and the reason a vanished SSD is a recovery case rather than a write-off.
Numbers clean: jot down today’s bytes-written figure, put a re-check in the diary for six months’ time, and that’s honestly the whole maintenance routine. Spare dropping, or integrity errors off zero: the flash is being unusually honest with you early — copy everything off while it still reads willingly, swap it out, and resist the urge to ‘double-check’ with stress tests, since each full scan burns more of exactly what’s running low. Stutters, freezes, a drive that disappears and comes back: those are controller symptoms, and power-cycle roulette only worsens them — back up now, in one unhurried pass. Already gone: stop reflashing, stop swapping cables in hope, and let a bench read it — our SSD & NVMe recovery service opens with a free diagnostic and a written quote. One SSD-only footnote: on internal drives TRIM wipes deleted files’ blocks within moments — so for an accidental deletion on an SSD, the backup was always the answer.
No. Health reflects the physical wear of the flash and the state of the controller; a format just lays a fresh file system on top and, if anything, spends a sliver more of the write budget. If formatting seems to ‘fix’ a misbehaving SSD, the fault was logical — and worth reading as a warning shot rather than a cure.
Never — defragmenting is a hard-drive habit that does an SSD active harm. With no moving head to optimise for, it achieves nothing while chewing through write endurance shuffling blocks about. Windows understands this and quietly runs TRIM in place of a defrag on SSDs; let it get on with it.
Not on any timer, but do treat it as end of service. At exhausted endurance a drive tends to slide toward read-only behaviour with a rising error count; get whatever’s on it off straight away, while reads are still good. What you shouldn’t do is keep it working ‘until it actually dies’ — that final failure isn’t always a gentle one.
Controller, firmware and chip-level SSD recovery in the lab — free 48-hour diagnostic, written quote first, no fix, no fee on most jobs.