WD Purple Pro 26TB versus 24TB is a narrow but expensive decision. The 26TB WD260PURP adds 2TB per drive over the 24TB WD241PURP, an 8.3 percent raw-capacity gain before RAID, filesystem overhead and recorder reservations.
Both current models share the important Purple Pro traits: CMR, SATA, 7200 RPM, 512MB cache, 287MB/s maximum transfer rate, 550TB/year workload rating, 2.5M-hour projected MTBF, five-year warranty, AllFrame AI and support guidance for 64 HD cameras plus 32 AI streams.
Choose WD Purple Pro 26TB when its live price premium over 24TB is less than about 8.3 percent, or when the extra 2TB per bay avoids a larger recorder or shorter retention window. Choose 24TB when the 26TB premium is higher than the capacity gain and bays are not the bottleneck.
Use this as the procurement-level screen before looking at live price rows.
| Decision point | WD Purple Pro 26TB | WD Purple Pro 24TB |
|---|---|---|
| Exact model | WD260PURP | WD241PURP |
| Capacity | 26TB | 24TB |
| Capacity gain | +2TB per drive | Baseline |
| Recording technology | CMR | CMR |
| RPM | 7200 RPM | 7200 RPM |
| Cache | 512MB | 512MB |
| Interface | SATA | SATA |
| Maximum transfer rate | 287MB/s | 287MB/s |
| Workload rating | 550TB/year | 550TB/year |
| Camera / AI guidance | Up to 64 HD cameras / 32 AI streams | Up to 64 HD cameras / 32 AI streams |
| Power | 6.2W read/write; 5.7W idle | 6.2W read/write; 5.7W idle |
| Best use | Bay-limited WD Purple Pro systems | Better value when priced materially lower |
| Main limitation | Small capacity gain can be overpriced | Lower retention per bay |
Raw decimal capacity before RAID, filesystem overhead and recorder reservations. The 26TB model adds 2TB per drive, an 8.3 percent gain over 24TB.
| Drive count | 26TB raw | 24TB raw | Raw difference |
|---|---|---|---|
| 4 drives | 104TB | 96TB | 8TB |
| 8 drives | 208TB | 192TB | 16TB |
| 12 drives | 312TB | 288TB | 24TB |
| 16 drives | 416TB | 384TB | 32TB |
| 24 drives | 624TB | 576TB | 48TB |
No exact in-stock live row is currently matched for WD260PURP / WD241PURP. Relevant live alternatives are shown so the page does not collapse into an empty catalogue.
Live prices · updated every 4-5 hours · last checked 1 hr ago · one side may be unavailable in exact live stock
| Model | Capacity | Recording | RPM | Workload TB/yr | Warranty | $/TB | Price | |
|---|---|---|---|---|---|---|---|---|
| 20TB ST20000VE002REFURB | 20TB | CMR | — | 550 | 5 yr | $25.00 | $500 | Buy |
| 18TB WD180PURZREFURB | 18TB | UNVERIFIED | — | — | — | $28.64 | $515 | Buy |
| 32TB ST32000VE000 | 32TB | CMR | — | 550 | 5 yr | $36.25 | $1160 | Buy |
Workload rating is recorded per part number from Seagate's datasheet for that exact model, not blanketed across the line — two drives of the same capacity can differ because they are different generations. A dash means the figure is not stated for that listing. Recording technology comes from the manufacturer's published CMR/SMR list; a model absent from that list is shown as UNVERIFIED rather than guessed. Rows priced above 3× this line's in-stock median are flagged and excluded from the winner callout and from every median we compute.
This table is computed from live DatacenterDisk rows when an exact in-stock match exists. It is intentionally blank for unavailable models rather than filled with stale prices.
| Live model | Drive price | $/TB | 1 drive | 4 drives | 8 drives |
|---|---|---|---|---|---|
| No exact in-stock row is available right now. Use the availability table for nearby live alternatives, then re-check the exact model before ordering. | |||||
The clean financial rule is simple: 26TB gives 8.3 percent more raw capacity than 24TB. If the 26TB drive costs more than 8.3 percent above the 24TB drive in the same condition and warranty channel, it is worse on raw price per TB.
That does not make it automatically wrong. If a recorder is full, the extra 2TB per bay can delay a chassis change or extend retention without touching the rest of the system. But the page should make the premium explicit rather than hiding it behind a larger number.
It usually stops making economic sense when the price premium exceeds the capacity gain and no other constraint is binding. For example, if 26TB is 15 percent more expensive than 24TB, the buyer pays more per terabyte unless the extra drive-bay efficiency has its own value.
The live price table is the right place to make that call because retail prices move. Do not hardcode a price from a past week into a drive standard. Compare the live 26TB and 24TB rows and check whether the 26TB premium is below, near or above 8.3 percent.
The 2TB gain can be meaningful in large systems. In four drives it is 8TB raw. In eight drives it is 16TB raw. In twenty-four drives it is 48TB raw. Those gains can cover several days of footage in some deployments and much less in high-bitrate 4K systems.
The only honest retention answer uses bitrate. Codec, frame rate, resolution, motion and RAID overhead dominate. A small capacity gain is valuable only when it lands on the right side of the required retention window.
Choose 24TB when the live price per TB is clearly better, the recorder's capacity limit is 24TB, or the retention target already has comfortable margin. The two models share the same major published workload figures, so there is no reason to overpay for a small gain you do not need.
24TB can also be easier to source in some channels. If a multi-drive order needs all drives at once, having enough units available at one condition and warranty status can matter as much as the spec sheet.
Choose 26TB when every bay is already spoken for, when the price premium is close to or below 8.3 percent, or when the extra raw capacity keeps a site inside a retention requirement without buying a larger recorder.
It also earns the premium when standardizing on the current top Purple Pro capacity simplifies spares across many sites. In that case, service consistency can matter more than a few dollars per terabyte on one recorder.
Two terabytes per drive, which is an 8.3 percent raw-capacity gain before RAID, filesystem overhead and recorder reservations.
The 26TB model is WD260PURP. The 24TB model is WD241PURP.
For raw price per TB, it stops making sense when the 26TB price premium is higher than the 8.3 percent capacity gain, unless bay scarcity or service costs justify the difference.
Yes. WD's current Purple Pro product brief lists both WD260PURP and WD241PURP as CMR.
No. Price per TB is the first screen, not the whole decision. Match recording method, interface, bay count, firmware support, warranty position and rebuild risk before accepting the cheapest row.
Specification claims on this page were checked against the pages below on 1 September 2026. Where a widely-repeated figure did not survive that check, we report what the source says now and say so in the text rather than repeating the familiar number.