Fountain Pen Review: Muji Fountain Pen

Sometimes, we discover there are great pens that have been around for quite some time that we never got around to reviewing. This is one of them.

Review by Laura Cameron 

 I found a new pen to love. A few weeks ago at knit night, Ana handed me a pen and told me to take it for a spin.  The pen was a Muji, an aluminum round fountain pen ($15) from the Japanese company, Muji.

 The pen is a super-slim, rounded aluminum pen with a textured grip, and a stainless steel nib.  It has a snap cap that posts in sort of unique way; the edges of the cap are super thin and fit into a thin channel hollowed out at the end of the pen. Mine is a fine nib and is marked “Iridium Point.” (Editor’s Note: Pretty sure that’s a Schmidt nib)

The Muji comes with cartridges, and I decided to go ahead and use them. I skipped the black cartridge that came with the pen, and played what Ana calls “cartridge roulette” – I dug into a canister of cartridges that she had sent me and emerged with one that I believe is Kaweco Palm Green ($2.10 for 6 cartridges).

I loved everything about this pen.  The pen is modern looking, slim and sleek at 20gms, but also has a surprisingly nice weight in my hand. The cartridge took almost no time to fill the pen, and it wrote immediately without problems.  I spent a little time testing it on a Pebble Paper Design notebook (review forthcoming) and had no problems with it at all. My lines were clean; the ink didn’t bleed or feather. 

Editor’s Note: I seriously need to update this chart! These are filled and capped/posted weights.

There isn’t a lot more to say about this pen, but it’s the one I reach for every time I go into my pen case. It’s fun and I feel like I found the perfect ink color to match.


The Muji fountain pen was previously reviewed here on the blog. If you’d like to read that review, you can see it here.

Laura is a tech editor, podcaster, knitter, spinner and recent pen addict. You can learn more about her knitting and tea adventures on her website, The Corner of Knit & Tea and can find her on Instagram as Fluffykira.

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9 comments / Add your comment below

  1. I’ve used this pen for a while now and like it quite a bit. There is also a converter available that fits it if you want to use bottled inks. It also fits easily in the pen loop on my legal pad holder. Many fountain pens are too wide to do that without stretching the elastic too much so it doesn’t spring back.

    1. I use a converter for mine, but had to put a spring from a cheaper ballpoint pen into the pen body to hold the converter in place since it’s come loose twice. The second time it came loose was very messy I just modified it last night, so hopefully I won’t have anymore leaks because I really like this pen

  2. It reminds me of an Exact knife. 🙂 I wonder if it writes as well as the knife cuts. Whoa, it looks an awful lot like the red stylus I have too.

  3. Where did you find the converter? When I asked at a NY store, the sales associate did not know anything about a converter. I didn’t see it on-line either.
    I have some wonderful fountain pens, but this little number is a real pleasure and the price is great!
    BTW, I’m a knitter too. ❤️

    1. It takes a standard size international converter. Those can be purchased from any of your favorite online or brick-and-mortar pen shops.

  4. Looks like the one I found that fit was a Schmidt K5 I bought on Amazon.

    Several of the web pages I found say it takes a Standard International Converter but at least one says it takes a Short Standard International Converter. Perhaps they are confusing this with the pocket pen version that Muji sells.

  5. Thanks! I’ll go for the Schmidt K5. You tried it, and it works. I have no need to experiment. I appreciate your quick reply.

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