What is the difference between willow and compressed charcoal?

Willow charcoal is light, soft and easily erased, making it ideal for initial sketches and loose work. Compressed charcoal is denser, produces darker marks and is harder to erase. Vine charcoal is similar to willow but slightly harder.

Do I need fixative for charcoal drawings?

Yes, charcoal drawings should be fixed with a workable or final fixative to prevent smudging. Apply in light, even coats. One 400ml can typically covers multiple large drawings. Workable fixative allows you to draw over it.

How long does a charcoal stick last?

A standard willow charcoal stick (about 15 cm long) covers roughly 800-1000 cm² depending on application thickness. Compressed charcoal covers less area per stick because the marks are denser.

What paper is best for charcoal drawing?

Use paper with good tooth (texture) such as Ingres paper, pastel paper, or cartridge paper with a rough surface. Smooth paper does not grip charcoal well. Heavier weights (150+ gsm) handle fixative better without warping.

ArtCalcs

Charcoal Calculator — Sticks, Pencils & Fixative

Estimate charcoal sticks, pencils and fixative needed for a drawing project.

Surface Width

Surface Height

Charcoal Type

Number of Drawings

Add 10% wastage

Recommended for breakage and waste

Price per Stick/Pencil (optional)

Price per Fixative Can (optional)

How We Calculate This

This calculator estimates charcoal materials using surface area and coverage rates per stick type.

Units needed = (Total area / Coverage per unit) x Wastage factor

Coverage rates used

Willow charcoal: ~800 cm² per stick
Vine charcoal: ~1000 cm² per stick
Compressed charcoal: ~600 cm² per stick
Charcoal pencils: ~400 cm² per pencil

Fixative coverage is based on approximately 20,000 cm² per 400 ml can.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always verify quantities before purchasing materials.