OKI B431d A4 Mono LED Laser Printer


Free 3 Year On-Site Warranty

  • Up to 38ppm Mono Print
  • 4.5 Seconds First page
  • USB & Parallel
  • Automatic Double Sided Printing
  • 1200 x 1200 dpi Print
  • 250 Sheet Input Tray
  • 100 Sheet Multi-Purpose Input Tray
  • 330MHz PowerPC405 Processor
  • 64MB (320MB Max) RAM
  • Windows & Mac Compatible
  • PCL5e, PCL6, Epson FX, IBM ProPrinter, PostScript3 emulation
Free Print Management Software OKI Mobile Printing
4.4 / 5 (6  reviews)
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  • Detailed  Specification
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  • Detailed  Specification
  • Cartridges & Accessories
  • Questions & Answers

Detailed Specification


Double Sided Printing Unit (Duplex) Duplex as Standard
Speed Monochrome Up to 38ppm Mono Print
First Page 4.5 Seconds First page
Product Group Output A4
Double Sided Printing Automatic Double Sided Printing
Printer Resolution 1200 x 1200 dpi Print
Warm Up Time 20 seconds from power save


Interface Type(s) USB & Parallel
Parallel Ports 1 x IEEE 1284 Bidrectional Parallel Parallel Port
Parallel Port Yes
USB Port Yes
USB Ports 1 x USB 2.0

System Specification

Processor 330MHz PowerPC405 Processor
Memory (Maximum) 64MB (320MB Max) RAM


Operating Systems Supported Windows & Mac Compatible

Media Handling

Paper Handling Input 1 250 Sheet Input Tray
Paper Handling Input 2 100 Sheet Multi-Purpose Input Tray
Additional Paper Tray optional 1 x 530 Sheet
Maximum Duplex Paper Weight 120gsm
Maximum Input Capacity 880 Sheet
Maximum Paper Size A4
Maximum Paper Weight 163gsm
Paper Handling Standard Output 150 sheets face down, 100 sheets face up
Paper Size A4, A5, B5(JIS), A6, Letter, Legal 13, Legal 14, Executive, Statement;
Paper Trays (Standard/Maximum) 2 (3)

Barcodes & Labels

Barcode Types 12 types of one dimension with 28 variations: UPC-A, UPC-E, EAN/JAN-8, EAN/JAN-13, Interleaved2of5, Code39, Code 128, EAN/UCC-128, CODABAR, ZIP+4POSTNET, Customer barcode, USPS Zip Barcode, 1 type of two dimension: PDF417

Duty Cycle

Monthly Duty Cycle 80,000
Recommended Max Print Volume 5000 Pages/Month


Mono or Colour Printer Mono
Technology LED Laser Printer
Dimensions 244.5mm (H) x 387mm (W) x 364mm (D) - Weight 12kg
Environmental Operating Temperature 10 to 32C - Humidity 20 to 80%
Noise Level 54dbA
Power Consumption Printing/Standby/Sleep Modes Typical: 550W; Max: 900W; Idle: 70W; Power Save: 8W
Product Type A4 Laser Printer
Carton Dimensions 48cm (W) x 34cm (D) x 47cm (H) - Weight 14kg

Consumable Info

Drum Life 25,000 Pages
Mono Toner Life 3,000 Pages


Printer Languages PCL5e, PCL6, Epson FX, IBM ProPrinter, PostScript3 emulation
Font Capabilities 87 scaleable PCL and 136 PostScript fonts, 2 bitmap fonts, OCR-A/B
Software Included Template Manager, Configuration Tool, Op-Panel Download Utility, Print Control Server, Print Control Client, Storage Device Manager

In the Box

In The Box OKI B431d mono printer, AC Cable (UK), CD/DVD (including Software/ Utilities/ Drivers and User Manuals), Setup Guide, Image Drum and Starter Toner = 1500 pages

Cartridges Included

Black 1500 Pages

Customer Questions & Answers

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Customer Reviews

Customer Reviews

Write a review for OKI B431d
  • 2.75 / 5
    Ian Daniel 15/1/2016
    3 Value
    2 Features
    3 Quality
    3 Perfomance

    Network Mgmt Needs Work

    It's not a bad printer but the management card doesn't support TLS. This means it will not work sending email alerts if you have Office 365 or to be honest quite a few other hosting services. We ended up having to use a second hosting package to send emails from this printer in plain text. Not really what you'd expect these days.

  • 5 / 5
    Steve Greatrex 21/3/2014
    5 Value
    5 Features
    5 Quality
    5 Perfomance

    Oki B431D

    I've used these printers for several months and have found them to be rock solid. To paraphrase another company's slogan, they do exactly what is says on the box. Good quality printing, reliable and quick. The extended warranty gives piece of mind.5 Stars deserved.

  • 4 / 5
    jeremy wing 12/3/2014
    4 Value
    4 Features
    4 Quality
    4 Perfomance

    OKI printer

    Would have liked the printer to have a paper counter.

  • 5 / 5
    Diane McDonald 3/9/2013
    5 Value
    5 Features
    5 Quality
    5 Perfomance

    OKI B431D

    Early days with our printer but so far so good. Excellent delivery. Easy to set up and really good quality prints produced quickly.

  • 5 / 5
    Rich Kendall 26/2/2013
    5 Value
    5 Features
    5 Quality
    5 Perfomance

    great service

    Jake in sales couldnt have been any more helpful than he was in supplying us with a printer that could still operate on the windows 98 platform (its an mot testing machine) thankyou for such an excellent company to deal with

  • 4.75 / 5
    O Lawton 19/1/2012
    5 Value
    5 Features
    5 Quality
    4 Perfomance

    Network Printer

    Excellent service in prompt delivery of ordered printer. Printer meets all expectations only reservation was slight difficulty in installation of driver software.

Promotion Terms

Free 3 Year On-Site Warranty

Buy this printer and you can receive a 3 year on-site warranty upon registration.

To claim your warranty please click here

Product must be registered within 30 days of purchase.

Free Print Management Software
OKI Mobile Printing
OKI & Mobile Printing

With the modern mobile workforce increasing at a rapid rate, and the growing popularity of tablets, smartphones and laptops, printing documents where and when you need them adds a whole new meaning to print on demand providing you have access to a compatible device.

Thanks to the many mobile applications available, you no longer have to be ‘back in the office’ to print and share documents essential to your business, customers or partners; promotional customer information, contracts - you can keep your business going whilst you are on the move.

Printing from Apple iPad or iPhone?
How to print to an OKI Printer from an Apple iPad

How does mobile printing work?

Cloud or mobile printing works by connecting to a wireless, networked or web enabled printer through a smartphone device or tablet, meaning you can print remotely from anywhere in the world, without having to connect directly to a printer nearby.

OKI products & Mobile Printing

OKI Colour, mono and multifunction printers are compatible with a number of applications available, so you can download an application of your choice that enables you to print to almost any device simply through a single mobile printing application.

Microtech Corp’s ePrint and Cortado Workplace, for example, are compatible with most printer manufacturer brands including OKI’s portfolio of mono and colour LED printers and MFPs.

Microtech Corp's website  - compatible with iOS and Android devices*

Cortado's website - compatible with iOS, Blackberry, Android and Symbian devices*

*please note: a PC or Apple Mac on the same wireless network may be required for full compatibility.
Trusted Review

Review Date: 3rd Aug 2010

Author: Simon Williams

Print Quality:

Print Speed:



Fast mono laser printers are still the stalwarts of most offices and OKI has revamped its mid-range offerings with new LED engines and built-in duplex print. In the process, they've updated the styling and improved the looks.

In a cream and light-grey case, the B431dn is neat and unobtrusive, as a good printer should be. The deep-set indentation in its top cover shows that it's designed to cope with relatively high workloads, where higher-capacity output trays are a necessity.

This capacity is matched by a 250-sheet input tray and a flip down 100-sheet multi-purpose tray for letterheads or envelopes. An additional tray, with a healthy 530-sheet capacity, is available as an option, to sit underneath the printer.

The control panel, which OKI points out is the same as on their new range of colour printers, thus making it easy to move from one model to the other, has a simple, four-way control disc for menu operations and two buttons for Online and Cancel. Indicator LEDs are mounted in the printer's front page to show Ready and Attention conditions.

There's a 2-line by 16-character LCD display, which would be a bonus if you could read it. As it is, without a backlight, with the display angled at around 45-degrees, and with a reflective acrylic face, it's very hard to see what it says. A couple of white LEDs would be all that was necessary for a backlight, so hardly a major cost burden.

The B431dn comes as standard with USB, Ethernet and legacy parallel connections and the whole machine is easy to set up. There's a two-part drum and toner cartridge, where the toner cartridge clips into the drum that carries it. The whole assembly dropped into place from the top, taking literally seconds to change.

Drivers are provided for Windows and OS X and are available for various Linux distributions. It's also compatible with a wide variety of network protocols.

OKI claims a top print speed of 38ppm for this machine, which is one of its selling points. As we include processing time in our measurements, the speeds we see are usually quite a bit lower, and our 20-page print clocked up just 25.5ppm. This is still a healthy print speed, but when we printed in draft mode, which in OKI’s case is really just a toner save mode, we still didn't get close to 38ppm.

This printer offers duplex print as standard and feeds paper very efficiently, with each completed page followed immediately by the first side of the next. We measured it at 17.1 sides per minute, making it possible to set the machine to duplex by default, without wasting a lot of time waiting for jobs.

A 15 x 10cm photo print on an A4 sheet took an impressively short 15 seconds at the printer’s top resolution and just 10 seconds printed at its default 600dpi. With most printers spending most of their lives asleep waiting for the next job, the wake-up times are important and this machine takes 20 seconds to heat its fuser up, which will add significantly to intermittent print times.

Print quality from the newly-engineered engine is extremely good. Text is sharp and clean, looking almost like traditional print. Even with toner-save switched on, it's still very readable, though a little light and grey.

Greyscale graphics are smooth, with very little blotchiness or banding. The only slight problem is a reduced range of grey shades, meaning that some colours in an original can be represented by very similar greys.

Photo reproduction, normally a bugbear with mono lasers, is very good, with lots of foreground detail and enough in the difficult, darker shadowed areas to still see what's going on. Although there are some differences between the default 600dpi resolution and the top level, true 1,200dpi, both are good and show virtually no banding.

This printer can handle a wider than normal range of paper sizes and you can load paper from A6 all the way up to a 1.2m banner. Useful at one end for ID cards and at the other for 'Well done on the sponsored Bat Watch' placards.

The toner cartridge is available in two capacities: 3,000 and 10,000 pages and the drum should need replacing only every 25,000 pages. Using the best prices we could find on the Internet gives a cost per page of 2.3p, including 0.7p for paper.

This is better than most of the mono laser printers and all-in-ones we've reviewed recently, though we have seen machines, like the Samsung ML-3471ND, which have a cost per page of under two pence.


This is a well-conceived, mid-range, laser-equivalent printer that uses OKI’s mature LED print technology to great effect. The new LED engine is quick and produces quality print of text, graphics and even photographic documents. Running costs are better than most and the only quibble we have is with the LED display. It could do with one of OKI’s high-intensity LEDs as a backlight.

All print speeds, running cost calculations and consumable life cycles are MANUFACTURER ESTIMATES based on 5% per page coverage. Images are used for illustration purposes only

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What's in the Box?

OKI B431d mono printer

AC Cable (UK)

CD/DVD (including Software/ Utilities/ Drivers and User Manuals)

Setup Guide

Image Drum and Starter Toner = 1500 pages

Running Costs

-All consumable life cycles are manufacturer estimates based on 5% per page coverage

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