Ultimate Guide to Mechanical Pencil Lead Sizes

What do the Different Lead Sizes Mean For Mechanical Pencils?

A mechanical pencil’s lead size refers to the diameter of the lead that the pencil writes with. The diameter of modern mechanical pencil lead is measured in mm.

The lead diameter of a mechanical pencil used to be measured in inches. When the pencil manufacturers converted to mm, this caused confusion as some manufacturers rounded up and others rounded down to the nearest mm for their labels and packaging.

This guide shows all the different lead sizes, what we use them for, and the manufacturers for each size.

So let’s dive in.

1. Mechanical Pencil Lead Size Comparison

There are many lead diameters listed by the different pencil manufacturers for their mechanical pencils.

However, some of the lead sizes are close enough in diameter to be considered the same size.

This is due to the diameter of the first mechanical pencil being measured in inches.

Today, we measure mechanical pencil leads in mm. When the manufacturers converted their measurements to mm, some rounded down, i.e., 0.35 mm rounded down to 0.3 mm diameter lead.

Other manufacturers rounded up, i.e., 1.1 mm, 1.15 mm, and 1.2 mm, are now considered 1.18 mm in diameter.

The diameter of 1.18 mm lead is close enough to 1.1, 1.15, and 1.2 mm to fit and work in these pencils.

1.1. 0.2 mm Mechanical Pencil Lead

Pentel is the only manufacturer that makes 0.2 mm pencil lead. It was first introduced in 1973 when they launched their PG2/PG2AD mechanical pencils.

Pentel Orenz 0.2 mm Mechanical Pencil

Buy on Amazon

These pencils are no longer manufactured by Pentel and have been replaced with the Pentel Orenz 0.2mm mechanical pencil.

Pentels AIN Stein 0.2 mm lead is available in HB, B, & 2B lead grades. Many people prefer the softer 2B lead as it is darker and partially negates the scratchiness of the tiny protective lead sleeve that it extends the lead from.

1.2. 0.3 mm Mechanical Pencil Lead

0.3 mm lead is a standard size that is often used by drafters for technical drawing.

0.3 mm Pencil Lead Manufacturers

• Faber-Castell
• Koh-I-Noor
• Pentel
• Pilot
• Rotring (branded 0.35 mm)
• Staedtler
• Tombow
• Uni
• Zebra

1.3. 0.35 mm Mechanical Pencil Lead

Rotring is one of the few companies that brands their pencil lead as 0.35 mm in diameter.

When the manufacturers switched from imperial to metric measurements for their lead diameters, most manufacturers rounded down to 0.3 mm to show the size on their packaging and labeling.

The lead is closer to 0.35 mm, with Rotring labeling their mechanical pencils and lead refills as 0.35 mm in diameter.

It makes no difference; you can use 0.3 mm pencil lead refills in Rotring 0.35mm mechanical pencils.

The Rotring 0.35 mm lead refills will fit in other manufacturers’ 0.3 mm pencils.

1.4. 0.4 mm Mechanical Pencil Lead

0.4 mm pencil lead is a typical size in Japan, but it is not manufactured by any non-Japanese pencil manufacturers.

The Pentel Graph Gear 1000, Pentel Graph 1000 for Pro, Pilot S3, S5, S10, Uni 552 Series, and the Uni Shift Pipe Lock 0.4 mm drafting pencils are the most popular pencils available with 0.4 mm lead.

0.4 mm Pencil Lead Manufacturers

• Pentel
• Pilot
• Uni

1.5. 0.5 mm Mechanical Pencil Lead

0.5 pencil lead is a standard size used for technical drawing and is widely available to buy. Pencils fitted with 0.5 mm lead are for writing fine narrow lines.

It is also popular with artists for detailed drawing.

Check out our Ultimate Guide to The Best Mechanical Pencil Lead to find out who makes the best lead refills.

0.5 mm Pencil Lead Manufacturers

• Bic
• Caran d’Ache
• Cross
• Faber-Castell
• Kaweco
• Koh-I-Noor
• Lamy
• Ohto
• Paper Mate
• Pentel
• Pilot
• Platinum
• Rotring
• Staedtler
• Tombow
• Uni-Ball
• Zebra

1.6. 0.7 mm Mechanical Pencil Lead

Drafters and artists use 0.7 mm pencil lead, but it is more widely used for writing.

The larger diameter of 0.7 mm lead compared to 0.5 mm strengthens it and makes it more break-resistant.

These characteristics make pencils fitted with 0.7 mm lead especially suitable for children and those who exert more pressure on the pencil’s tip when writing.

0.7 mm Pencil Lead Manufacturers

• Bic
• Caran d’Ache
• Cross
• Faber-Castell
• Kaweco
• Koh-I-Noor
• Lamy
• Ohto
• Paper Mate
• Pentel
• Pilot
• Platinum
• Rotring
• Staedtler
• Tombow
• Uni-Ball
• Zebra

1.7. 0.9 Mechanical Pencil Lead

Drafters primarily used 0.9 mm pencil lead to create precise lines. Most 0.9 mm pencils are professional quality technical pencils with longer lead sleeves. This is to protect the lead and act as a guide for rulers and straight edges.

0.9 mm Pencil Lead Manufacturers

• Bic
• Caran d’Ache
• Cross
• Faber-Castell
• Kaweco
• Koh-I-Noor
• Lamy
• Ohto
• Paper Mate
• Pentel
• Pilot
• Platinum
• Rotring
• Staedtler
• Tombow
• Uni-Ball
• Zebra

1.8. 1.0 mm Mechanical Pencil Lead

1.0 mm lead, and 0.9 mm lead are the same size. Many manufacturers rounded down to 0.9 mm lead on their labeling by introducing metric as the standardization.

Although Rotring and Faber-Castell sell their lead as 1.0 mm in diameter. It makes no difference both 0.9 mm, and 1.0 mm work equally well in pencils branded 0.9 mm and 1.0 mm.

1.0 mm Pencil Lead Manufacturers

• Faber-Castell
• Rotring

1.9. 1.1 mm Mechanical Pencil Lead

1.1 mm lead is interchangeable with 1.18 mm lead, as their diameters are both considered to be close enough to work in both size pencils.

1.1 mm Pencil Lead Manufacturers

• Rite in the Rain

1.10. 1.15 mm Mechanical Pencil Lead

1.15 mm Mechanical Pencil Lead is interchangeable with 1.18 mm lead, as their diameters are both considered to be close enough to work in both size pencils.

1.15 mm Pencil Lead Manufacturers

• Retro 51
• Worther

1.11. 1.18 mm Mechanical Pencil Lead

Yard-O-Led was one of the first companies to manufacture mechanical pencils. They called these propelling pencils and had a lead diameter of 3/64 inches.

Other manufacturers who made their own propelling pencils adopted this size.

When manufacturers converted to decimal, they either rounded up or down 1.18 mm is the closest diameter, but some manufacturers chose 1.1 mm and 1.15 mm.

1.1 mm, 1.15 mm, and 1.18 mm pencils leads are interchangeable as their diameters are very close.

1.18 mm pencil lead is also known as vintage pencil lead.

This is because Yard-O-Lead adopted 3/64 of an inch for the lead diameter of their mechanical pencils and other early pioneers.

1.18 mm Pencil Lead Manufacturers

• E&M
• Kaweco
• Yard-O-Led

1.12. 1.3 mm Pencil Lead

1.3 mm pencil lead is ideal for drawing and shading and marking out thicker lines. Due to its larger diameter, it is not really suitable for everyday writing.

Although Paper Mate makes a 1.3 mm mechanical pencil with a triangular-shaped barrel that is designed for young children.

1.3 mm Pencil Lead Manufacturers

• Kokuyo
• Paper Mate
• Pentel
• Staedtler

1.13. 1.4 mm Mechanical Pencil Lead

German Pencil manufacturers including Faber-Castell, Lamy & Stabilo are the only manufacturer that uses 1.4 mm in their pencils.

Lamy ABC children’s mechanical pencils were originally fitted with 3.15 mm lead. But they switched to 1.4 mm as it is robust and easier to write more legibly with.

Stabilo specially designed and manufactured 1.4 mm lead for their Easyergo 1.4 ergonomic mechanical pencil.

This pencil is designed for children aged 8 years and over and is available in left and right-handed versions.

For more information check out our guide The 6 Best Mechanical Pencils for Children.

1.4 mm Pencil Lead Manufacturers

• Faber-Castell
• Lamy
• Stabilo

1.14. 2.0 mm Mechanical Pencil Lead

2.0 mm lead is used for drawing and is the standard size for clutch pencils /lead holders. These are different from mechanical pencils as the lead is held in place and released by a clutch mechanism.

For more information about the clutch, pencils check out our guide to the different pencil types.

Below 2.0 mm most mechanical pencil lead is not sharpened with the exception of Uni Kuru Toga pencils that have a unique self-sharpening mechanism.

Lead Pointers are a special type of sharpener that is available for lead diameters 2.0 mm and above.

This allows artists to have more control of the sharpness of the lead point which becomes blunt quite quickly when shading and sketching.

2.0 mm Pencil Lead Manufacturers

• Caran d’Ache
• Faber-Castell
• Kaweco
• Kitaboshi
• Koh-I-Noor
• Ohto
• Pentel
• Rotring
• Staedtler
• Uni

1.15. 2.5 mm Mechanical Pencil Lead

2.5 mm lead is not a common size and the Czech manufacturer Koh-I_Noor is the only company that currently manufactures a 2.5 mm clutch pencil.

2.5 mm Pencil Lead Manufacturers

• Koh-I-Noor

1.16. 3.15 mm Mechanical Pencil Lead

3.15 mm pencil lead is a popular size for quickly shading in large areas when drawing. The Lamy Scribble & Worther Shorty being particularly favored by artists.

The Stabilo Easyergo 3.15 is an ergonomic mechanical pencil for young children aged 5 years +. It is the largest diameter pencil lead for writing and its lead is advanced via a push-button mechanism.

3.15 mm Pencil Lead Manufacturers

• Faber-Castell
• Lamy
• Stabilo
• Worther

1.17. 3.2 mm Mechanical Pencil Lead

Kaweco is the only company that manufactures 3.2 mm lead which is the size that they have traditionally used in their best-selling Kaweco Classic Sport Pencils.

Recently they have slightly reduced the diameter o their 3.2 mm lead to making them work better in other manufacturers’ 3.15 mm pencils.

3.2 mm Pencil Lead Manufacturers

• Kaweco

1.18. 3.8 mm Mechanical Pencil Lead

3.8 mm lead is a broad lead that is used for sketching and drawing. The Pilot Croquis sketching pencil takes 3.8 mm lead and is one of the best-known pencils fitted with 3.8mm lead.

The Pilot Croquis lead is advanced by twisting the barrel.

3.8 mm Pencil Lead Manufacturers

• Koh-I-Noor
• Pilot
• Kutsuwa

1.19. 5.2 mm Mechanical Pencil Lead

The Spanish Stationery company Milan is the only one that makes 5.2 mm pencils and lead refills.

1.20. 5.6 mm Mechanical Pencil Lead

5.6 mm is the largest diameter of pencil lead used for drawing, sketching, and shading. The two most popular pencils that use 5.6mm lead are the Kaweco Sketch Up and the Koh-I-Noor 5340 clutch pencils.

5.6 mm Pencil Lead Manufacturers

• E&M
• Kaweco
• Koh-I-Noor

2. Can You Put Any Size Lead In A Mechanical Pencil?

You cannot put any size lead in a mechanical pencil as each pencil is manufactured to take a lead that is a specific diameter.

A mechanical pencils lead is extended from a protective sleeve that has a diameter fractionally larger than the diameter of its lead.

3. What is the Standard Mechanical Pencil Lead Size?

Mechanical pencils are used for many different tasks including writing, technical drawing, sketching, and shading.

There are over 15 different lead diameters for mechanical pencils and therefore there is no standard lead size.

There are also 10 different lead grades available for mechanical pencils, check out The Complete Guide to Mechanical Pencil Lead Grades for more information.

4. What are the Most Common Mechanical Pencil Lead Sizes?

The most common lead sizes are 0.5 mm for fine writing, 0.7 mm for general-purpose writing and 2.0 mm for sketching and shading.

5. What are Drafting Pencil Lead Sizes?

Drafting pencils are used to draw consistent line widths. Their lead sizes are 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.7 mm, and 0.9 mm.

The Staedtler 925 25 is the only drafting pencil with a 2.0 mm lead diameter.

Check out our Ultimate Guide to Drafting Pencils for more information.

6. What Is The Smallest/Thinnest Mechanical Pencil Lead?

Buy Pentel 0.2mm Pencils & Refills on Amazon

0.2 mm is the thinnest mechanical pencil lead size, made by Pentel for their Orenz mechanical pencils.

7. How Do You Measure Mechanical Pencil Lead Size?

If you don’t know the size of the lead in your mechanical pencil there are three ways to find out.

1. Measure the diameter of the pencil lead with vernier calipers to find out the size of the lead.

2. Carefully check the barrel of the pencil to see if it has been marked on it ie 0.5/.5 requires to be refilled with lead refills 0.5 mm in diameter.

3. Try gently pushing a known replacement lead diameter into the end of the lead sleeve. Don’t force it or break it as it will jam and need to be removed with a pencil lead clean-out rod.

8. What are Vintage Mechanical Pencil Lead Sizes?

Vintage mechanical pencils used to take leads that were manufactured to imperial sizes. Yard-O-Lead was one of the first manufacturers and their lead was 3/64 inches in diameter.

Modern pencil lead is measured in mm and 1.1 mm, 1.15 mm, 1.18 mm diameter may fit a vintage pencil but it will be a case of trial and error.

It may also be that the manufacturer of the vintage pencil used a bespoke size and there is no modern-day equivalent.

9. What are Bic Mechanical Pencils Lead Sizes?

Bic mechanical pencil leads are either 0.5, mm, 0.7 mm, or 0.9 mm in size.

10. What are Cross Mechanical Pencil Lead Sizes?

All new Cross pencils are fitted with 0.7 mm lead, but they used to make pencils with 0.5 mm, 0.7 mm and 0.9mm leads diameters. Check out our Ultimate Guide to Cross Pen & Pencil Refills for more information.

11. What are Papermate Mechanical Pencil Lead Sizes?

Papermate mechanical pencil leads are either 0.5, mm, 0.7 mm, or 0.9 mm in size.

12. What are Parker Mechanical Pencil Lead Sizes?

Parker currently only makes the Parker Jotter mechanical pencil with 0.5 mm lead.

13. What are Sheaffer Mechanical Pencil Lead Sizes?

Sheaffer no longer makes mechanical pencils but modern used pencils were either 0.5 mm or 0.7 mm.

References

Lamy

Kaweco

Staedtler