Free companion to your mineral-rights offer guide

Understand the numbers behind an offer.

An offer is built on assumptions. Explore how income, decline, timing and risk affect a scenario, then see which facts need a closer look before you sign.

This calculator shows arithmetic using your inputs. It does not determine market value, verify ownership or produce an appraisal. MRX provides education only and does not buy mineral rights.

Get the free book and fillable worksheets · Prepare a human underwriter conversation

For interests already paying royalties

Model a producing-income scenario.

Use an average of representative royalty statements paid to you, after statement deductions. Exclude one-time adjustments you cannot explain. You already have your ownership share in that payment; do not multiply it by your royalty decimal again.

The rate and horizon starting values below are editable teaching assumptions, not recommended rates for your property. No result appears until you enter your income and calculate.

No producing income or missing statements? Leave this calculation unused. That does not mean the mineral interest has no value.

See the formula and what it leaves out

Year t income = monthly income × 12 × (1 − decline rate)t−1. Present value = the sum of each modeled year's income ÷ (1 + discount rate)t. Year one uses a full year at your starting income; payments are discounted at each year end.

This simplified constant-decline model includes no terminal value, undeveloped acreage, future wells or lease bonus. It holds prices and deductions within your starting income assumption. It does not forecast engineering reserves, seasonal payments, taxes, buyer costs or lease/title changes. The discount rate reflects an assumption about timing and risk; it is not a promised investment return.

The comparison cases change decline by 10 percentage points and discount by 5 percentage points, bounded between 0 and 100. They illustrate sensitivity, not a confidence interval or a sale-price range. Buyers may use different records, forecasts and commercial assumptions.

Compare the acreage basis of a written offer.

Use gross tract acres and your documented fractional mineral ownership. Net mineral acres and net royalty acres are different measures. A division-order payment decimal or a lease royalty rate is not your mineral ownership fraction.

For example, a documented 1/4 mineral interest is 25%. If the basis is unknown, ask for the controlling records rather than guessing.

Formula: gross acres × mineral ownership share = estimated net mineral acres. Written offer ÷ those acres = the offer per net mineral acre. This standardizes your stated inputs; it does not establish fair price or that the offer covers the same rights, depths and conditions.

What a landman checks before a purchase.

  1. What is actually owned? Legal description, chain of title, probate, reservations, depths and mineral versus royalty interest.
  2. What is being conveyed? Match the offer, agreement, deed and exhibits. Clarify retained rights and effective dates.
  3. What supports the income? Lease terms, division orders, payment history, deductions, operator and available production records. Engineering forecasts and local market evidence may be needed.
  4. What could change the price? Ask which quantities and title assumptions are preliminary, what adjustments are allowed and what records must support them.
  5. What makes closing possible? Identify the buyer, signer, funding party, review deadline, extension rules and payment/release sequence.

Landmen, engineers, valuation professionals and attorneys have different roles. An online calculation cannot substitute for their property-specific work. AAPL due-diligence guidance · NARO valuation methods.

If the offer drops, ask for the explanation in writing.

Compare the original and revised amount, interest, acreage, conditions and dates. Request the calculation and supporting records. A documented ownership adjustment can be legitimate; an unexplained reduction, newly introduced condition or pressure to sign deserves further questions. Do not assume either deception or fairness from a number alone.

Download the fillable comparison worksheets, record what is unresolved, and book a free educational conversation with a human underwriter. Elena is the fictional AI scheduling guide; she helps arrange the appointment.

Calculations run in your browser. Calculator inputs are not submitted to MRX. Refreshing or leaving the page clears them; save your own notes if you want to discuss the assumptions.