Free Tool
Division Order Decimal Calculator
Verify the decimal interest shown on your division order. Enter the numbers from your lease and title documents — the result is accurate to 8 decimal places, the industry standard.
Enter as a fraction (1/8) or a percentage (12.5%)
Formula: Decimal Interest = (Net Mineral Acres ÷ Unit Acres) × Royalty Rate × Tract Participation Factor
This is how operators typically calculate your decimal. If the division order they sent shows a different number, that's worth a closer look.
How to calculate your division order decimal
Your decimal interest is the share of a well's revenue you're entitled to. Operators use it to calculate every royalty check, so verifying it before you sign a division order matters. The standard formula is:
Decimal Interest = (Net Mineral Acres ÷ Unit Acres) × Royalty Rate
Worked example
Say you own 10 net mineral acres in a 640-acre drilling unit, with a 1/8 (12.5%) lease royalty. Your decimal is (10 ÷ 640) × 0.125 = 0.00195313. Paste that into the Royalty Income Estimator to project the income.
What you need
- Your net mineral acres in the unit (from your deed or title opinion)
- The drilling unit size in acres (from the plat or the operator)
- Your lease royalty rate (from your oil and gas lease)
Frequently asked questions
What is a division order decimal interest?
It's the exact fraction of a well's revenue you're owed, written as a long decimal — (net mineral acres ÷ unit acres) × royalty rate. It controls every check from that well.
How do I find my net mineral acres?
They should appear in your mineral deed or the title opinion from when the property was leased. If you can't find them, a landman or title attorney can determine them from county records.
Which royalty rate should I enter?
Use the rate stated in your lease — for example 1/8 (12.5%) or 3/16 (18.75%).
What if the operator's decimal doesn't match mine?
Investigate before signing. Recheck your acres, the unit size, and the royalty rate; if it still differs, ask the operator for their breakdown. Learn more in how royalties are calculated.
Want saved calculations, multi-tract tracking, or help reading your actual documents? See Pro.