Our take
The HP LaserJet Pro 400 color M451dn is a print-only color laser rated up to 21 pages per minute in both black and color. HP documents automatic print duplex and a recommended monthly range of 750 to 2,000 pages. The dn configuration does not have the built-in Wi-Fi described for the separate M451nw and M451dw variants. HP marks the model discontinued. The product materials describe the four-cartridge color system, but the saved packet avoids uncertain tray details and does not confirm the exact Ethernet port configuration. Historical ASIN mapping, current supply, and used-unit condition remain unknown.
A wired color print queue needing automatic duplex at a modest workload, when a discontinued model can be inspected before purchase..
Do not choose it if built-in Wi-Fi, copy or scan functions, a confirmed network port, or a current supported model is required.
Pros & cons
What could work for you, and what to consider before buying.
What works in its favor
- HP documents color output and automatic duplex for the M451dn specifically.
- The 750–2,000 page monthly recommendation helps distinguish modest use from heavier office work.
- A 21 ppm rating in both black and color gives a direct basis for output comparison.
What to weigh up
- The M451dn is a printer only and does not add copy, scan, or fax functions.
- Wireless belongs to separate nw and dw variants, not this dn configuration.
- HP marks the model discontinued; listing identity, condition, and tray configuration are unknown.
The key details
| Model covered | M451dn |
|---|---|
| Main functions | Print only |
| Print output | Color laser; up to 21 ppm black and color; 750–2,000 recommended pages/month |
| Two-sided printing | Automatic duplex; four toner colors; built-in wireless not documented |
Performance figures are manufacturer claims. Source checked October 4, 2026. Regional models and included accessories can differ.
What the features mean for you
Color printing without all-in-one functions
HP identifies the M451dn as a color printer rather than an MFP. It is suited to color documents produced from a computer, not to an office that expects one device to scan originals, copy forms, or send faxes. The manufacturer lists up to 21 pages per minute in black and color. That specification can help compare output classes, but real speed varies by page content and setup. If most jobs are black-only or require capture and forwarding, an alternate workflow may fit better.
Automatic two-sided output is documented
The product page and model-specific source confirm automatic duplex for the M451dn. The printer turns pages during two-sided print jobs, avoiding manual reloading for recurring reports. That capability is separate from scanning, which the device does not provide. A used printer still requires a sample to confirm that the mechanism operates in its present condition. Because HP marks the model discontinued, ask about page count, feed reliability, included toner, and return terms rather than treating the original feature list as a guarantee about an individual unit.
Keep the dn, nw, and dw configurations separate
HP's variant notes identify built-in Wi-Fi on the M451nw and M451dw, not the M451dn. The exact suffix therefore matters for a shared installation. The saved packet does not use Ethernet as a matching fact because the inspected records do not establish the precise port configuration needed for this profile. A buyer planning a cable-based network should verify the actual interface and model label before purchase. A general M451 family result or a seller's short headline cannot resolve the hardware installed in a particular machine.
A moderate monthly range, with tray facts left open
HP recommends 750 to 2,000 pages per month for the M451dn. This interval gives a reasonable comparison for modest office use, but it does not describe a particular device's age or remaining service. HP source materials describe the model's paper path inconsistently, so tray capacity is not used to match or rank it. That choice keeps the product profile tied to facts the saved exact-model sources support. Check the included trays and media path on a listing if capacity will affect a regular job.
Four color cartridges do not establish current supply
HP's source describes a four-toner color configuration. This establishes the intended print system, but it does not establish whether a present offer includes usable cartridges or whether compatible replacements are currently easy to obtain. A buyer should check cartridge numbers, remaining levels if available, and whether the printer produces a clean sample. No cost-per-page calculation or current consumables claim is made from the old product specification. For a discontinued color model, supply and maintenance questions can matter as much as its duplex feature.
Verify exact identity and seller condition
The historic ASIN B06X9X1FG1 is not verified as an exact M451dn offer. The product therefore uses a tagged search link rather than a direct Amazon URL. Ask for the printer label showing M451dn or product code CE957A, a color and duplex sample, the actual ports, included trays, toner status, page count, maintenance history, and return terms. The current page may describe toner support rather than a new printer offer. Present stock, condition, price, and accessory bundle remain outside the saved evidence.
What else to compare
Compare a wireless M451 variant only after verifying its exact suffix, or choose a newer color model if lifecycle support is a priority.
Before you buy
Does the M451dn include automatic print duplex?
Yes. HP's exact M451dn material documents automatic two-sided output.
Does this version have built-in Wi-Fi?
No. HP assigns Wi-Fi to separate M451nw and M451dw variants, not the M451dn.
Is Ethernet confirmed for this product profile?
The saved exact-model packet does not establish the precise Ethernet configuration, so it remains unknown here.
Where can I check the current price?
Use the Amazon link for current offers. Check the exact model, seller, product condition, delivery, and return terms. This page does not display a live price or confirm stock.
Sources & review basis
We use the following manufacturer documentation for the product features above. Our suitability notes and buying advice are editorial judgments based on those features, not measured performance results.
- HP LaserJet Pro 400 color M451dn product page ↗ — checked October 4, 2026.
- HP M451dn model, status, output, duplex and variant-specific Wi-Fi notes ↗ — checked October 4, 2026.
- HP M451dn specification fields for recommended volume, print rate and color cartridges ↗ — checked October 4, 2026.
The decision
The M451dn is a narrow color duplex printer fit for a wired modest-volume workflow after the exact ports and used condition are checked.
Is it the right fit?
Check the exact model and today’s offers on Amazon.