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HP 645A Black Original LaserJet Toner Cartridge, C9730A

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Product # C9730A
  • Original HP cartridge, designed for reliability and consistency
  • Standard size, when you need just one
  • ~13,000 pagesSee all Specs

Selected options

(16 more available)
HP 645A Black Original LaserJet Toner Cartridge, C9730A

3% back in HP Rewards

Get the best results from your HP printing system. HP Smart technology[1] and chemically-grown toner formulas in HP 645A LaserJet Toner Cartridges work with your printer to deliver accurate, consistent color and reliable, cost-effective performance.

Take pride in high-quality prints with Original HP Toner.

The choice you can trust to help avoid reprints and wasted supplies. Choose Original HP Supplies, designed for reliability and consistency.

Outstanding color

Consistently accurate color and precise images with HP chemically-grown toner Optimal print quality with new image mode feature[3]

Reliable, cost-effective

Cost-effective operation with all-in-one HP toner cartridges HP Smart technology[1] tunes particle charge for reliable results Rated A+ for service and reliability, PC Magazine August 2003

Easy to use

Easy to use automatic alerts, on-line ordering with HP Smart printing technology[1] When a color cartridge runs out, continue printing with the black cartridge[2] Easy to use and install with HP Smart printing technology[1]

Technical details

Color(s) of print cartridges

Black

Print technology

Laser

Page yield (black and white)

~13,000 pages

Page yield footnote

Approximate yield based on 5% average coverage. Actual yields vary considerably based on content of printed pages and other factors.

Operating temperature range

59 to 77°F

Storage temperature range

-4 to 104°F

Operating humidity range

20 to 80% RH

Storage humidity

10 to 90% RH

Recycled content in cartridge

17%

Package dimensions (W x D x H)

19.69 x 6.3 x 10.43 in

Package weight

6.38 lb

Warranty

HP's Premium Protection Warranty. This HP product is warranted to be free from defects in materials and workmanship.

What's in the box

Toner cartridge; Recycling guide
HP 645A Black Original LaserJet Toner Cartridge, C9730A is rated 3.7 out of 5 by 9.
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Rated 5 out of 5 by Mary Fran from Great features! The HP 645A Black toner cartridge is easy to replace and the printing is excellent! The cartridge also has a long life span.
Date published: 2021-08-20
Rated 5 out of 5 by GG2812 from Easy ordering Always buy original HP products they work the best and keep our machine running smoothly.
Date published: 2020-04-23
Rated 5 out of 5 by Peggy1133 from Creates Fantastic Photos and Documents! We purchase original HP products for our HP printer and we are never disappointed. We produce some presentations, however, our printer is used daily for printing design plans in order to quickly see how the plans will display to our clients. We are always pleased with the documents we are able to print using the HP printer and its toner cartridges!
Date published: 2020-03-26
Rated 5 out of 5 by Gail69 from Purchase and delivery Easy online purchase and quick delivery, product always great
Date published: 2019-09-27
Rated 5 out of 5 by Steeleye from always great I have been using this product with my laserjet 550 for many years and it never disappoints.
Date published: 2013-07-09
Rated 5 out of 5 by Somamac from Defective Cartridge / High Cost This cartridge was ordered to test whether my 5550n or the cyan cartridge in it (ordered in May 2011) was defective causing a memory tag message to come up on the printer display. The new cartridge worked, indicating it was the older cyan cartridge, and not the printer, that had a problem. (I had never had this problem with any 5550n cartridge ordered previously.) The new cyan cartridge has worked flawlessly so far. The HP cartridges for this printer are very good ... and, in my view, unreasonably expensive. Even with the discount offered for multiple purchases over the course of a year ("My Print Rewards"), I am continually forced to rethink whether it makes economic sense to use cartridges from HP for this printer. Replacing all 4 cartridges cost well over $1100. Astonishing!
Date published: 2011-11-19
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Our office needs a HP LaserJet CP4005n Black printer cartridge 642A What black ink cartridge will work in this printer

Asked by: Bethel Leg Office
Thank you for your question! The HP LaserJet CP4005n is an older printer. The toner cartridges for this printer are no longer available from HP. The compatible toner is the HP 642A. You may be able to locate these cartridges from one of our retail partner websites.
Answered by: HP Team Grant
Date published: 2024-03-12
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Return and exchange information
Eligible purchases from Nov 1 - Dec 25, 2025, can be returned or exchanged until Jan 15, 2026, or 30 days after delivery, whichever is later. A 15% restocking fee may apply. For details, please visit: https://www.hp.com/us-en/shop/cv/returnsandexchanges
Country/Region :   United States