WD Red Prices - CMR or SMR by Model Number

Read the suffix, not the name

WD Red is three product lines wearing one brand, and the only reliable way to tell which one you are holding is the last four letters of the part number. Red Plus and Red Pro are conventionally recorded across their ranges per Western Digital's own data sheets. Plain WD Red contains shingled models. The marketing name on a retail listing does not settle it, and we have watched listings label a plain-Red part number as a Red Plus.

The decoder above is built from the models we have verified against WD documentation rather than written from memory, so it cannot drift from what we can actually show you. Each row links the WD document behind its answer, and each example model number has its own page carrying that source.

One row in that table is highlighted, and it is the row that catches people. The EFAX suffix is widely repeated as a synonym for shingled recording, and it is not one. Western Digital's own client recording-technology list names the 2TB, 3TB, 4TB and 6TB Red drives as shingled and states that all other capacity points use conventional recording. That makes WD80EFAX, WD100EFAX and WD120EFAX conventionally recorded drives with the suffix everyone treats as a warning sign.

The practical consequence is that a decoder built on suffixes alone is wrong at three capacities, and a buyer who learned the rule from a forum thread will reject a perfectly good 8TB drive or, worse, apply the same reasoning in the other direction. The full part number resolves it. The suffix narrows it.

If you have the drive in front of you, the part number is printed on the top label, usually beginning WD followed by the capacity digits. Our exact-model resolver takes a pasted part number, including OEM suffixes, and answers from the manufacturer's document.

The three tiers, with the specifications WD currently publishes

Red Plus is the mainstream NAS tier. Western Digital's current data sheet rates it at 180TB per year with a three-year limited warranty, conventionally recorded throughout, at rotational speeds that vary by model between 5400 and 7200. The models in that document run from the 2TB WD20EFPX to the 12TB WD120EFGX.

Red Pro is the tier above. WD's current Red Pro data sheet states 550TB per year and a five-year limited warranty for every model in the line, at 7200rpm, conventionally recorded, from the 2TB WD2002FFSX up to the 26TB WD260KFGX. That last point is worth stating precisely because it contradicts a figure repeated across ranking guides: the 300TB per year often quoted for Red Pro does not appear in WD's current data sheet for any model in the line.

Plain WD Red is the tier the decoder exists for. WD's own Red product brief prints SMR against the 2TB, 3TB, 4TB and 6TB models, footnoted as device-managed shingled recording. Those drives are not defective and they are not bad value for the workload they suit, and they are the wrong tool for a parity array.

On the capacity ceiling, our answer is narrower than what circulates. Ranking guides quote a Red Plus ceiling of 14TB on one page and 22TB on another. Neither figure appears in WD's current Red Plus product brief or data sheet, both of which top out at 12TB. Western Digital's own store does list a 14TB Red Plus SKU that those documents do not cover, so the honest position is that the documented ceiling is 12TB and a 14TB part exists outside the current documentation. The 22TB figure appears to be Red Pro's range attributed to the wrong tier.

Where a model in our tables predates the current data sheet, its workload, warranty, rotational speed and cache render as dashes rather than being copied from a neighbouring model. That produces a table with visible gaps, which is correct: an inferred specification printed in a table is indistinguishable from a sourced one to whoever is reading it.

What happened in 2020, and what changed

This is the history behind every suffix question people still ask about this line, and it is worth setting out plainly with the sources attached rather than gesturing at a controversy.

In April 2020 it emerged that Western Digital had been shipping drive-managed shingled recording in WD Red drives marketed for NAS use without stating it on the specification sheets. Western Digital responded publicly on its own corporate blog in a post titled "On WD Red NAS Drives", writing that it regretted "any misunderstanding" and committing to update its marketing materials and to publish more information about the technology.

That post also contains the most useful technical admission in the whole episode, and it is WD's own words rather than a community claim. Western Digital wrote that the increased amount of sustained random writes during ZFS resilvering, which it described as similar to a rebuild, causes a lack of idle time for device-managed shingled drives to execute internal data management tasks, resulting in significantly lower performance. In the same post it recommended its conventionally-recorded Red drives instead, naming Red Pro and what it then called the forthcoming Red Plus.

Alongside the blog post Western Digital published a model-level list of which of its client drives use shingled recording. The April 2020 version of that list named the 2TB, 3TB and 4TB Red drives; the version dated July 2020 and the current Red product brief also include the 6TB. Both state that all other capacity points use conventional recording, which is the sentence that makes the EFAX rule capacity-dependent rather than absolute.

The Red Plus branding was introduced in the aftermath to designate the conventionally-recorded NAS line, which is why a drive bought before 2020 can say simply "WD Red" on a CMR mechanism while a drive bought today needs the word Plus to promise the same thing. Western Digital faced class-action litigation in the United States and Canada over the non-disclosure, which was subsequently settled; a settlement is not a finding of liability, and we are not characterising it as one.

What changed materially is disclosure rather than technology. Shingled recording still exists in the plain Red tier, WD still sells it, and it is now stated in the product brief with a footnote explaining the implementation. That is the outcome worth knowing: the information is available, it is just not in the product name.

ZFS, TrueNAS and why the rebuild is the moment that matters

Shingled recording overlaps data tracks like roof tiles to raise density. Reading is unaffected. Writing is affected when the drive has to modify data underneath an existing track, because the tracks laid over it may have to be rewritten too. Device-managed shingled drives absorb incoming writes into a conventionally-recorded staging area and reorganise them during idle time, which is why they behave normally in ordinary use and why the problem is invisible until it is not.

A ZFS resilver or a RAID rebuild removes both halves of that design at once. The volume of writing exceeds the staging area many times over, and there is no idle time to reorganise because the pool writes continuously until the operation completes. Western Digital's own blog post describes exactly this mechanism and its consequence.

The reason it matters more than the word "slower" suggests is what a rebuild is. It is the operation during which the array has spent its safety margin: in single parity one drive is already gone and a second failure destroys the pool. Every remaining drive is read end to end under sustained load, often for the first time in years, and the drives are typically the same age and from the same batch as the one that just failed. Extending that window is not an inconvenience, it is holding the array in its most vulnerable state for longer while doing the thing most likely to expose another weak drive.

For TrueNAS and any ZFS pool the practical instruction is short and it is Western Digital's own recommendation rather than ours: use the conventionally-recorded drives. Red Plus and Red Pro both qualify across their current lines. Our TrueNAS guidance covers pool layout and the wider drive selection, and CMR versus SMR is the cross-brand lookup with the per-model badge.

One caveat that applies to advice everywhere on this subject: if you already have a shingled drive in a pool, the worst response is to force a resilver today to remove it. Confirm your backups are current, avoid operations that trigger a full rebuild, and replace it at a moment of your choosing rather than creating the exact event you are trying to avoid.

The tier ladders, and where each one is the right buy

Red Plus is the correct default for a household or small-business NAS, and the case is stronger than the price difference suggests. A four-bay array at home generates a fraction of the 180TB per year the tier is rated for, the conventional recording removes the question this whole page is about, and the money saved against Pro buys capacity, which is the thing you actually notice.

Red Pro earns its premium in three specific situations rather than in general. High bay counts, where vibration between drives stops being theoretical and the higher rating has something to do. Sustained write activity, where the workload rating is a real constraint rather than a comfortable margin. And capacity, because the Pro range reaches sizes the Plus range does not, at which point the comparison ends and there is only one option. The live premium at every capacity is the number that decides the edge cases.

Plain WD Red is the trap tier and the table above shows it with the badge visible rather than omitting it. We list the shingled models because their presence is the warning: somebody searching for a cheap Red drive will find these, and finding them here with the recording technology stated and the source linked is better than finding them on a listing that does not mention it. That is not a recommendation.

The one genuinely good legacy buy is the EFRX generation. Those are the pre-2020 WD Red drives, conventionally recorded under WD's own list, and they appear now as refurbished or old stock at rates the current lines do not approach. For a secondary array, a backup target, or a build where a drive failing means replacing a drive, they are sensible. Our recertified drive guidance covers what to check on arrival and how to think about the warranty position, which is the real cost of buying this way.

Across brands, the sibling comparison worth reading is WD Red Pro against Ultrastar, where the price paradox is that WD's enterprise line frequently undercuts its own NAS line per terabyte. Seagate's equivalent range is on our IronWolf hub, and the tier logic there mirrors this one closely.

How to check the drive you already own

If the array is already running, you do not need to open the case. Every operating system will report the model number of an attached drive, and that string is what settles the question.

On a Synology or QNAP unit the model number appears in the storage manager against each drive. On Linux, lsblk with the model column or smartctl against the device node will print it. On Windows, the device manager lists it under disk drives. On macOS, System Information under Storage. In every case what you want is the full string beginning WD, not the friendly name the interface may show.

Paste that string into our exact-model resolver and it will return the recording technology with the Western Digital document that establishes it. It handles OEM suffixes, so a label reading WD40EFAX-68JH4N0 resolves to the WD40EFAX answer without you having to trim it.

If the answer comes back shingled and the drive is in a pool, the guidance above applies: do not panic, do not force a resilver, verify your backups and plan the swap. If it comes back conventional, you have your answer and there is nothing to do.

And if the model is one we have not verified, the resolver says so rather than guessing. Those searches are logged and they decide which models get verified next, so an unanswered query is useful rather than a dead end.

Frequently asked questions

Sources

Specification claims on this page were checked against the pages below on 7 August 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.

1. Western Digital - WD Red Plus HDD data sheet (WesternDigital.com, 2025)
   Used for: per-model part numbers from WD20EFPX to WD120EFGX stated as CMR; 180TB/year annualized workload rate; 3-year limited warranty; rotational speed and cache per model; up to 8 drive bays
2. Western Digital - WD Red Plus HDD product brief (WesternDigital.com, 2025)
   Used for: the documented Red Plus capacity range topping out at 12TB; CMR stated for the line; NASware firmware description
3. Western Digital - WD Red Pro HDD data sheet (WesternDigital.com, 2025)
   Used for: 550TB/year annualized workload rate and 5-year limited warranty stated for every model in the line, from the 2TB WD2002FFSX to the 26TB WD260KFGX; 7200 RPM; CMR; cache per model; up to 24 drive bays. The 300TB/year figure repeated in ranking guides does not appear in this document for any Red Pro model
4. Western Digital - WD Red Pro HDD product brief (WesternDigital.com, 2025)
   Used for: Red Pro capacity range and CMR statement for the line; RV sensor and multi-axis shock sensor inclusion
5. Western Digital - WD Red HDD product brief (WesternDigital.com, 2025)
   Used for: SMR printed against the 2TB, 3TB, 4TB and 6TB plain WD Red models, footnoted as device-managed SMR. This is the current WD document that makes the plain-Red shingled models a stated fact rather than a community finding
6. Western Digital - WD Red NAS 3.5-inch data sheet (WesternDigital.com, 2025)
   Used for: plain WD Red per-model specifications, cache, rotational speed class and warranty term
7. Western Digital - On WD Red NAS Drives (corporate blog post) (blog.WesternDigital.com, April 2020)
   Used for: WD naming its 2TB, 3TB, 4TB and 6TB WD Red drives as device-managed SMR; the statement that sustained random writes during a ZFS resilver leave DMSMR drives no idle time to execute internal data management tasks, resulting in significantly lower performance; the recommendation of WD's CMR-based Red drives including Red Pro and the forthcoming Red Plus; "We regret any misunderstanding"; the commitment to update marketing materials
8. Western Digital - WD client SMR SKU list (April 2020 slide) (blog.WesternDigital.com, April 2020)
   Used for: the model-level list of WD client drives using SMR as first published, and the statement that all other capacity points use CMR
9. Western Digital - WD SMR SKU list (July 2020 revision) (blog.WesternDigital.com, July 2020)
   Used for: the revised model-level SMR list. This is the document that makes the EFAX suffix capacity-dependent rather than a synonym for SMR: only the smaller Red capacities are named, so WD80EFAX, WD100EFAX and WD120EFAX are CMR
10. Western Digital - Shingled magnetic recording HDD technology (white paper) (WesternDigital.com, 2024)
    Used for: the mechanism itself: overlapping track layout, the conventionally-recorded media cache used to absorb incoming writes, and the reliance on idle time to reorganise data in device-managed implementations
11. The Register - WD faces class action lawsuit over SMR drives (TheRegister.com, 29 May 2020)
    Used for: the filing of class-action litigation over the non-disclosure, and its date
12. Tom's Hardware - WD hit with class action lawsuits over SMR hard drives in the US and Canada (TomsHardware.com, 2020)
    Used for: the existence of litigation in both the United States and Canada
13. Tom's Hardware - WD moves to settle SMR HDD false advertising class action (TomsHardware.com, 2021)
    Used for: that the litigation was settled. We state this as a settlement and nothing more: a settlement is not a finding of liability and we do not characterise it as one
14. Tom's Hardware - WD addresses SMR controversy with new Red Plus hard drives (TomsHardware.com, 2020)
    Used for: the introduction of the Red Plus brand as the designation for the CMR NAS line
15. DatacenterDisk Research - Live WD Red price and stock database (DatacenterDisk.com, Live)
    Used for: every price, $/TB figure, stock state, condition badge, premium calculation and price-history verdict on these pages
16. DatacenterDisk Research - CMR vs SMR - which drives are which (DatacenterDisk.com, 2026)
    Used for: the cross-brand recording-technology lookup and the per-model resolver behind every badge