Calculate the copper-to-gold ratio from entered USD quotes and compare two periods with optional 10-year Treasury yields.
Copper/Gold Ratio Formula
The calculator uses two formulas, one per mode.
Current ratio mode:
Trend compare mode:
- Copper price: market quote for copper, converted to U.S. dollars per pound.
- Gold price: market quote for gold, converted to U.S. dollars per troy ounce.
- Ratio: copper price divided by gold price using the standardized units above.
- Previous Ratio / Current Ratio: the ratio computed at two points in time.
- 10-year Treasury yield: optional input in the trend mode, used for a descriptive comparison of directions; two observations do not establish a correlation.
The current ratio mode standardizes whatever quote units you enter (cents per pound, dollars per metric ton, dollars per gram, dollars per kilogram, dollars per pound, dollars per troy ounce) before dividing. It also reports the same-weight ratio, which compares copper and gold per troy ounce so you can see how cheap copper is by weight. The trend compare mode runs the ratio at two points in time and shows the percent change, the point change, and an optional comparison to the 10-year Treasury yield.
Reference Tables
Illustrative heuristic bands for the quote ratio (copper $/avoirdupois lb divided by gold $/troy oz). These are not universal historical ranges or validated investment signals:
| Ratio | Reading | Common interpretation |
|---|---|---|
| 0.0025 or above | Copper relatively strong | Higher illustrative band; no economic prediction |
| 0.0018 to below 0.0025 | Middle range | Middle illustrative band; no economic prediction |
| Below 0.0018 | Gold relatively strong | Lower illustrative band; no economic prediction |
Unit conversions used inside the calculator:
| From | To | Factor |
|---|---|---|
| ¢/lb | $/lb | ÷ 100 |
| $/metric ton | $/lb | ÷ 2204.6226 |
| $/troy oz | $/lb | × 14.5833 |
| $/gram | $/troy oz | × 31.1035 |
| $/kg | $/troy oz | × 0.031103 |
| $/lb | $/troy oz | ÷ 14.5833 |
Worked Examples and FAQ
Example 1: Current ratio. Copper trades at $4.50 per pound and gold trades at $2,300 per troy ounce. Ratio = 4.50 / 2300 = 0.001957. That falls in the illustrative middle band; it is not a forecast.
Example 2: Trend compare. Previous prices were copper $4.10 and gold $2,000, giving 0.002050. Current prices are copper $4.50 and gold $2,300, giving 0.001957. Using unrounded ratios, Change = ((4.50 / 2300) / (4.10 / 2000) − 1) × 100 ≈ −4.56%. Gold has outperformed copper over the period.
Why divide copper $/lb by gold $/troy oz? This quote convention is used in macro comparisons with Treasury yields. Its numerical level depends on the chosen mass units; only the same-weight ratio is a dimensionless relative price. Use comparable quote timing and spot or futures bases.
What does the same-weight ratio show? It converts copper to dollars per troy ounce and divides by gold per troy ounce. It tells you how copper is priced compared with gold for the same amount of metal. The number is small because gold is far more expensive per ounce.
Why compare the ratio to the 10-year yield? The ratio and yields can move together in some periods, but their relationship varies. This calculator compares entered changes using illustrative direction thresholds; it does not diagnose bond-market stress or predict yields, growth or investment returns.
Does the quote unit matter? No, as long as you select the right unit in the dropdown. The calculator standardizes everything to copper $/lb and gold $/troy oz before computing the ratio.
