CJ's Laundromat sits at Unit GJ, Pacific Tower, Shop 1/119A Worcester St in Christchurch's central city, with a 4.0 Google rating.
The trick to a good laundromat visit is matching the machine to the load: commercial washers come in a range of drum sizes, so a small wash in the biggest machine costs more than it needs to, while an overloaded small one leaves clothes barely rinsed. Commercial machines also use far less water than a home washer, so a half-dose of detergent does the job — too much leaves residue on clothes and gunk in the drum. Regulars time the wash and dry at roughly an hour all up, bring something to read, and favour weekday lulls over busy weekend afternoons.
For anyone living or working around the CBD without a machine of their own, CJ's on Worcester St puts a proper wash within easy reach.