ASA verdict
The Muji 0.38 Gel Ink Pen deserves much of its reputation, but mainly as a practical fine line writing tool. Its strengths are consistent: a lightweight polypropylene body, clean minimalist design, refill compatibility, wide colour range, and a crisp 0.38 mm point that suits small handwriting and planner use.
Why it earned this score
Writing Experience
10.0 /10
Fine, controlled, and reliable for neat writing. Reviewers consistently position it as a strong everyday 0.38 mm option rather than a luxury writing experience.
Ink Smoothness
10.0 /10
The Muji 0.38 delivers a smooth and consistent writing experience for an extra fine gel pen.
Smudge Resistance
9.0 /10
The Muji 0.38 dries reasonably quickly on most paper, but it is not among the fastest-drying gel pens.
Comfort
8.0 /10
The slim barrel looks clean and feels light, but it lacks a cushioned grip, so longer writing sessions may not suit everyone.
Value for Money
10.0 /10
It is inexpensive, refillable, widely available through Muji.
Buying guidance
Good to know
- Tip size: 0.38 mm.
- Body: polypropylene.
- Refillable with Muji gel ink pen refills.
Before you buy
- Buy it for fine control, not maximum smoothness.
- Test it before pairing with other highlighters.
- The body is very light, which some users love and others dislike.
- The grip has no rubber cushioning.
- Refills are easiest to source through Muji.
Editorial insight
The Muji 0.38 is valued for precision, simplicity, colour choice, and price. The main caution is ink behaviour under highlighting, not everyday writing.
Bottom line
ASA recommends it for neat everyday writing, but not as the best gel pen for highlighter heavy notes.