This calculator helps you turn your own quoted charges into a buyer's bid ceiling or a seller's proceeds estimate. All amounts use pounds sterling. It does not estimate a domain's market value, recommend a bid or supply any provider's fees.
Use the actual gross quote
Check which charges apply, what each percentage is charged on, whether a renewal is included, and whether a minimum or tiered fee changes the total. The calculator supports one percentage of the bid or sale amount plus separately entered fixed charges. A fee with a different basis, a minimum charge or a changing rate needs a separate check against the actual quotation.
For a buyer, enter a single gross percentage uplift on the bid. Include all applicable percentage-based tax on the bid and on its fee in that combined uplift. For example, if a quote supplies a fee exclusive of tax, first establish its actual gross effect on the bid from that quote. Do not enter the same tax again as a fixed or other cost. No tax rate is assumed here.
Enter fixed charges, renewal and other allowances as gross cash amounts including applicable tax. Do not include a cost twice. The result is a cash budget before any later tax recovery; it does not calculate eligibility to recover tax. In seller mode, proceeds are after the entered charges and before any tax on your proceeds.
Worked buyer example
Fictional arithmetic, not a provider quotation or a price recommendation. Suppose the all-in budget is £1,000, the gross percentage uplift is 10%, fixed charges are £25, renewal is £15, other costs are £0 and the bid increment is £0.01.
The amount available for bid plus percentage charges is £1,000 − £25 − £15 = £960. The unrounded ceiling is £960 ÷ 1.10. Rounded down to the entered increment, the maximum bid is £872.72. The percentage charge rounds up to £87.28, so the total is £1,000.00 with £0.00 remaining.
With the same assumptions and a £5 increment, the bid ceiling becomes £870.00, the percentage charge is £87.00 and the total is £997.00, leaving £3.00. The calculator treats increments as multiples from zero. A venue may use a different starting bid, reserve or bid ladder, so check which bid it actually permits.
If the entered fixed costs exceed the budget, no bid fits. If the remaining budget cannot cover a positive bid at the selected increment, the calculator says so. A zero result is not a recommendation to place a bid.
Worked seller example
Fictional arithmetic, not a provider quotation. Enter a £1,000 sale amount, a 10% gross commission, a £25 fixed charge and £20 of other selling charges. The commission is £100 and total charges are £145, leaving £855 before any tax on your proceeds.
The calculator allows negative proceeds. For example, if the charges exceed a small sale amount, the result shows the additional cash needed rather than silently changing it to zero. Check unsold-listing charges separately: a proposed sale calculation does not establish what you pay if no sale completes.
Rounding and limits
The calculator uses whole pennies for money and accepts percentages to four decimal places. It rounds a percentage charge up to the next penny, then rounds the buyer's bid ceiling down to a multiple of the entered increment. This is a conservative budgeting convention; your provider's invoice rounding may differ.
Each money input must be between £0.00 and £999,999,999.99, and a bid increment must be at least £0.01. Percentages must be between 0% and 1,000%. Enter plain decimal numbers without commas or currency symbols. Blank, negative, non-numeric or over-precise entries do not produce a result. Editing an input clears the previous calculation until you calculate again.
Keep the assumptions with your decision
After calculating, print the assumptions sheet or download it as TXT or CSV. It includes every numeric input, the rounding basis and the complete cost breakdown. No domain name is requested. The tool does not save your entries, so keep the file if you need a record and recalculate when your quote changes.
The interactive calculator needs JavaScript. Without it, use the worked examples above and the printable valuation worksheet. You can also keep your supporting evidence in the domain research workbook.
Use the valuation guide to explain why a possible purchase is justified, the auction guide to prepare for bidding and the selling guide to check listing and handover terms. A cost calculation complements those decisions; it cannot establish a domain's appraised value.