Compare To Mechanical Pencil Lead
With mechanical pencils, the right lead can make the difference between a forgettable writing experience and one bordering on sublime. Whether you’re using a 40-cent Bic or a $400 Montblanc, it’s the lead that determines how a pencil writes. When choosing your lead, the first thing to consider is the choice of lead hardness grade. Softer leads are darker and smoother than harder leads, but also smear more and get used up faster. For everyday use, we recommend staying in the range of H to 2B.
Once you’ve chosen a hardness grade, you’ll need to consider which brand of lead to use. Different brands do perform differently, and the best one for you depends on how you use your pencils most. Let’s take a look out our top pencil lead recommendations, after which we’ll delve into a more extensive comparison of all our lead brands.
Uni NanoDia leads have the best overall balance of smoothness, darkness, break-resistance, and longevity, making them a great choice for any task. The name NanoDia is for the nano-diamond particles used in the lead to provide better strength and smoothness than typical leads. They are available in sizes from 0.3 mm to 0.9 mm and a variety of hardness grades (4H to 4B in 0.5 mm size), so you can enjoy NanoDia leads no matter your pencil and lead grade preferences.
Alternatively, Uni Kuru Toga leads are similar to the NanoDia leads but with a unique twist. The outer layer of the lead is soft, while the inner core is hard. When used in a Kuru Toga auto lead rotation pencil, this helps the lead to form and retain a sharp point more easily. Even if you don’t use a Kuru Toga pencil, however, the Kuru Toga leads still hold a point well, especially if you rotate your pencil occasionally while using it. (Many people do this without even realizing it.)
Best Lead for Writing and Sketching: Pilot Neox
Pilot Neox leads are smoother and darker than the NanoDia leads, with a lubricated feel that makes for an effortless writing and sketching experience. This is due to the Neox leads’ high-purity graphite. With fewer impurities in the lead, the layered graphite sheets that make up the lead are able to slide onto the page with minimal resistance. The tradeoff for this smoothness is reduced longevity—we found the Neox wrote about two-thirds as long as the NanoDia leads before getting used up. Neox leads are among the easiest to erase, making them great for correcting mistakes or adding highlights to drawings. Like the NanoDia leads, Neox leads come in a wide range of sizes and hardness grades.
Alternatively, Rotring Tikky leads are the smoothest leads we have and just as dark as the Neox leads. They get used up much faster than the Neox leads, however, and they’re less break resistant and less easily erasable than the Neox leads.
Best Lead for Math Homework and Diagrams: Pentel Ain Stein
Uni NanoDia Lead
Pentel Ain Stein Lead
Super-smooth leads may be great for free-flowing words and drawings, but for intricate math formulas and diagrams, having lead with a bit more feedback gives a better sense of precision and control. Pentel Ain Stein leads have a nice amount of feedback, neither too scratchy or too smooth. They also have better smear resistance than the Neox or NanoDia leads—a valuable feature for keeping notes and assignments legible after being kept in a binder or stack of papers over time. Ain Stein leads come in the widest selection of grades and sizes, including the ultra-fine 0.2 mm size (perfect for pairing with the Pentel Orenz 0.2 mm mechanical pencil).
Alternatively, Tombow Mono-WX leads give the most feedback and are the longest lasting of all our leads. They are don’t erase as easily as the Ain Stein leads, however, and they come in a limited selection of sizes and grades.
Best Colored Lead: Pilot Color Eno Neox
Pilot Color Eno Neox
Pilot Color Eno Neox Lead
If you want a colorful alternative to normal graphite leads, we recommend Pilot Color Eno Neox leads. They work in any 0.7 mm mechancial pencil and are more erasable and break resistant than most colored leads (though still less than graphite leads). They come in eight colors, including the popular Soft Blue—a favorite among artists for preliminary sketches due to its non-photo-blue properties and ability to be easily edited out of digitally scanned artwork.
Check out our guide to colored mechanical pencil leads for an extensive comparison of all our colored leads.
Let’s take a look at how all of our leads compare in terms of selection, smoothness, darkness, break resistance, longevity, erasability, and smear resistance. For now, we’ll focus on leads available in the most common sizes and grades. There are a few leads only available in less-common sizes like 0.9 mm, 1.1 mm, or 1.3 mm, but we’ll look at them further down.
Pentel Ain Stein leads have the widest selection of sizes and hardness grades, followed closely by Uni NanoDia and Pilot Neox leads.
Note that some lead sizes are named differently by different brands even though they are physically identical and perfectly interchangeable. Specifically, 0.3 and 0.35 mm leads are interchangeable, as are 0.9 mm and 1.0 mm leads.
Among HB leads, the smoothest are the Rotring Tikky and Pilot Neox leads. The leads with the most feedback are the Tombow Mono-WX, Tombow Mono Graph, and Lamy M-Series leads.
Very smooth leads give a luxurious writing and sketching experience, but for more precise work like math homework and technical drawing we prefer the control offered by leads with more feedback. Softer leads are smoother than harder leads, so for even more smoothness or feedback, try using a different lead grade.
Among HB leads, the darkest are Pilot Neox and Rotring Tikky leads. The lightest leads are Pentel Ain Stein, Tombow Mono Graph, and Tombow Mono-WX leads. That said, darkness is directly correlated with hardness, so the differences between leads of the same grade are subtle.
If you have a heavy hand, broken leads can be a constant frustration. Many of our leads are specially formulated to be stronger than typical leads. When we tested the leads against each other, some leads had average break resistance while others were noticeably stronger. Within these two groups, however, their break resistances were close enough to be indistinguishable.
Harder leads tend to be more break-resistant than softer leads, so if break resistance is more important to you than darkness or smoothness, we recommend trying an H or 2H lead, as well as a lead-guarding mechanical pencil like the Zebra DelGuard.
Break Resistance Table
The longest-lasting lead was the Tombow Mono-WX, followed by the Pentel Ain Stein and Uni NanoDia leads.Some leads last longer than others before wearing down. In addition to being cost-efficient, longer lasting leads also save you from having to extend the lead as often.
To measure the longevity of each lead, we tested how many lines of x’s we could write with 1 mm of lead. Longevity is closely related to hardness, which is closely related to darkness. Because of this, lighter and harder leads tend to be longer-lasting than softer and darker leads.
The easiest leads to erase were the Pilot Neox and Uni Hi-Uni leads. The Staedtler Mars lead took the most effort to erase, but all of the leads erased completely from normal copy paper with enough erasing. All of the leads erased easily from Rhodia paper.
We tested the leads using our bestselling Uni Boxy eraser, seeing how well each lead erased with a single pass of the eraser and when fully erased with repeated passes.
All of the leads smeared, but some less than others. The least-smearing lead was the Tombow Mono Graph lead, followed by the Pentel Ain Stein, Staedtler Mars, and Tombow Mono-WX leads. If smear resistance is especially important to you, we recommend using a harder lead grade like H or 2H, which will be more smear-resistant than softer leads.
Smearing can be caused by rubbing the page with your hand or simply by pages rubbing against each other in a notebook or stack of papers. We tested HB leads from each brand on copy paper and Rhodia paper to see how much they smeared when rubbed over with a single, heavy pass of a thumb.