An amount stated before tax and an amount stated including tax need different calculations. The Tax Calculator offers exclusive and inclusive modes so you can add your entered rate to a base amount or separate that rate from an existing total.
Use exclusive mode for a known base
Enter PKR 1,000 with an illustrative rate of 18% in exclusive mode. Tax is PKR 180 and the total is PKR 1,180. The example rate is a hypothetical input for explaining the formula, not a statement of the rate applicable to a Pakistani product or seller.
Exclusive mode multiplies the base by the entered percentage, then adds the resulting tax amount. It assumes the amount entered is the complete base to which that one rate applies.
Use inclusive mode for a known total
Switch to inclusive mode and enter PKR 1,180 with the same 18% assumption. The tool divides the total by 1.18, returning PKR 1,000 before tax and PKR 180 tax.
Taking 18% directly from PKR 1,180 would produce PKR 212.40, which is wrong for this inclusive example. The tax portion is included in a larger total; its percentage was originally applied to the smaller base.
Determine the applicable treatment before calculating
The calculator does not decide whether an item is taxable, which jurisdiction applies, whether a seller must register or what records a return requires. It uses the rate and amount that you supply. Consult the relevant documents and an appropriate adviser when establishing those inputs.
Mixed rate invoices require separate calculations for their different bases. One average rate can hide how individual lines were treated. The same caution applies to charges that are excluded from a taxable base under your actual arrangement.
Separate item tax from tax on a service fee
If a payment provider charges tax on its own fee, the base may be the provider fee rather than the customer invoice. Payment Gateway Fee Calculator and Marketplace Fee Calculator model entered tax on fees in that specific context.
Keep the mode, base definition and entered rate beside the result. Displayed rounding may differ from an invoice that rounds tax on each line before adding totals. This tool provides arithmetic only and does not generate tax returns, registration advice or SEO settings. For reconciliation, compare the calculated components with the source invoice instead of assuming a matching gross total proves every line is correct.