Janka Hardness Explained What it measures • Typical ranges • What it does (and doesn’t) tell you
Janka hardness is one of the most common numbers used to compare wood species. This page explains what the test measures, how to interpret the number, and the limits of using Janka as a performance shortcut. Reference-only: no product recommendations.
Janka hardness measures the force required to press a steel ball into wood to a defined depth. Higher numbers generally indicate a harder wood species. Janka is useful for relative comparison, but it does not describe the full performance of a finished product.
Common Janka hardness numbers (reference)
| Material / Species (common name) | Typical Janka (lbf) | General relative category | Notes (reference-only) |
|---|---|---|---|
| Pine (varies) | ~380–870 | Softer | Wide range depending on type; numbers are approximate. |
| Red Oak | ~1,290 | Mid-range | Often used as a familiar reference point in charts. |
| White Oak | ~1,360 | Mid-range | Commonly close to red oak but not identical. |
| Hard Maple | ~1,450 | Harder | Often referenced for higher hardness among domestic species. |
| Hickory / Pecan (varies) | ~1,820+ | Harder | Numbers vary by species and source; shown as a general reference. |
| Brazilian Cherry (Jatoba) | ~2,300+ | Very hard | Commonly listed high-Janka example; verify source if comparing. |
Reminder: These numbers are reference-only and can vary. Compare like-for-like sources when possible.
Quick explainers
What the Janka Test Measures
Janka measures resistance to a specific kind of indentation. A steel ball is pressed into the wood to a defined depth, and the force is recorded. Higher numbers generally indicate a harder wood under this test.
What Janka Does NOT Measure
- Finish scratch resistance: coatings/topcoats can scratch differently even on the same species.
- Impact performance of a full product: construction and backing layers can change outcomes.
- Moisture behavior: hardness does not equal moisture resistance.
- Stain/chemical resistance: not what Janka is designed to evaluate.
Why The Same Species Can Show Different Janka Numbers
Wood is a natural material. Values can vary due to sample selection, moisture content, growth conditions, and whether the data is an average, a range, or a single tested sample. Different charts may cite different sources.
How To Use Janka Responsibly
Janka is best used as a relative species hardness reference, not a complete performance ranking. If you’re comparing products, read Janka alongside construction details (core, veneer thickness, finish) and any relevant lab tests.
FAQ
Is a higher Janka number always “better”? ⌄
Not automatically. Higher Janka means harder under the Janka indentation test, but overall performance depends on the full product construction and finish system.
Does Janka predict scratch resistance? ⌄
Not directly. Many scratches happen in the finish/topcoat, and different coatings behave differently. Janka measures wood indentation resistance, not coating scratch performance.
Why do charts disagree on Janka values? ⌄
Different sources may use different sample sets or report averages vs ranges. Natural variation and reporting style can lead to different published numbers for the same species.
Should I compare Janka numbers across different product categories? ⌄
Use caution. Janka is specific to wood. Other categories may use different indentation or abrasion tests that are not directly comparable.