Anatomy of a Fineliner - Art-n-Fly

Archival ink fine line pens, aka “fineliners”, are the ideal tool when you want to avoid smudging or smearing (like when using with markers) or for writing applications from cute doodles to decorate an encouraging sign for your favorite person or for putting notes on ultra-thin pages like a bible. If you want to know how fineliners differ from your standard fountain pen, read ahead!

Ink (the biggest differentiator!)

 The major difference between fineliners and regular pens is in the ink. Other pens typically use dye-based, water-soluble inks which makes them unsuitable for use with other media like watercolor and markers. They also penetrate into paper and cause bleeding which makes it difficult to draw on fine paper without disastrous results. Dye-based inks do tend to be more vibrant, so if the desired result is vibrancy and they’re being used on suitable paper, standard ink can be a great choice. 

Fineliners use pigment-based ink, which sits on the surface of paper rather than penetrating so it can be used on even the thinnest pages without bleedthrough. They’re waterproof so you can expect them to withstand use with just about any other media without smearing, which is why they’re a favorite companion to alcohol markers. They’re also non-toxic and have almost no odor.

ultra fine fineliner

Archival ink is permanent, durable, and chemically stable. This means it withstands UV rays, chemical degradation, damage from oils (for example from hands), moisture, and solvents. This is the reason you’ll often see fineliners used not only in art, but also in drafting, labs, on tiny jewelry tags, in museums, and in any application where permanence is prized. It’s lightfast so it can be exposed to adverse conditions without losing its color, and it has a neutral pH so that it does not affect the surfaces on which it is applied.

Typical pigment particles are too large to consistently pass through fine tips, however, we have a process to reduce the particle size to 1/25000thof an inch to allow it to flow. 



The tips of our fineliners come in 7 sizes (the ultra-fine 003 is sold separately). The sizes come from a technical pen size indication system and have no direct relationship to the pens’ tip sizes. They are plastic needle-point tips that are firm and create consistent line sizes.


Line Size (mm)

 Line Size (in)


0.15 mm

0.006 in


0.2 mm

0.008 in


0.25 mm

0.009 in


0.3 mm

0.01 in


0.35 mm

0.014 in


0.45 mm

0.018 in


0.5 mm

0.02 in


There’s a specific size that’s ideal for each application. The finest pen size, 003, is best for extremely detailed work like writing on diamonds, but some artists like this size best for a subtle outline. However, this tip should only be used on smooth surfaces like paper or glass as it can easily become clogged. For example, wet paint can clog the tip and prevent the ink from flowing. This tip can also take very little pressure due to its fine size, so exercise caution.

The largest tips, 05 and 08, are ideal for everyday writing, doodling and drawing on their own, and any other application where a bolder stroke is preferred. These tip sizes can withstand more pressure and feel sturdier, plus they are not prone to clogging so you can use them on a variety of surfaces.

The mid-sized 01, 02, and 03 are more versatile and can be used interchangeably to create a variety of looks, Zentangle patterns, for hand lettering, or just about any other application where a high-quality pen is needed.


Fineliners were originally created to be a disposable alternative to technical pens. For this reason, they’ve historically been used by architects and engineers to create consistent line widths. Nowadays they are primarily used for art. They work beautifully with most media as they don’t smudge or bleed, lending themselves perfectly to illustration. 

Another common application of fineliners are comics and manga because of the pens’ rich, crisp archival ink and the variety of line sizes.

Journaling and writing are another great use of fineliners as they don’t bleed through most pages. Many people use them on religious texts.

How do you use your fineliners? We love hearing about unique uses; let us know in the comments!

1 Response


September 13, 2020

I love these markers

Leave a comment