WoodSwatch · The Wood Ledger
Koa
Acacia koa
Also known as: Hawaiian Koa, Koa Acacia
Technical Spec Sheet
2026-07-14

Reference grain swatch
- Janka Hardness
- 1,170 lbf (5,204 N)
- Avg. Dried Weight
- 610 kg/m³ (38 lb/ft³)
- Specific Gravity
- 0.58
- Type
- Tropical hardwood
- Grain
- Straight to wavy, often with stunning curl or figure
- Texture
- Medium
- Durability
- Moderately durable, resistant to decay
- Region
- Oceania
- Sustainability
- Restricted — Vulnerable - endemic to Hawaii, limited supply, protected
Overview
Koa is Hawaii's most prized native wood, renowned for its stunning figure and importance in ukulele and guitar making. Its golden to reddish-brown color and often spectacular curl make it highly sought after. The species is endemic to Hawaii with limited supply, making it a precious and protected resource.
The heartwood ranges from golden to reddish-brown, often with dramatic curl, fiddleback, or feather figure. It has a medium texture with straight to wavy grain. Dried weight averages 610 kg/m³ with a Janka hardness of 1,170 lbf. The wood is moderately dense with excellent acoustic properties.
Workshop Notes
Blunting Effect
Moderate
Gluing
Good gluing properties
Finishing
Excellent - takes oil and polish beautifully, figure enhances with finish
Steam Bending
Good steam bending characteristics
Scent
Mild, pleasant when worked
Assessment
Strengths
- Stunning figure
- Excellent for ukuleles
- Works well
- Beautiful finish
Weaknesses
- Limited supply
- Expensive
- Can crack if dried too fast
- Protected species
Common Uses
Ukuleles · Guitars · Furniture · Turnery · Veneer · Fine woodwork