← All postsPyalm Books
Jun 17, 2026

How to Calculate a Discount (and Work Backwards from the Sale Price)

Percentage-off maths is simple until you need the original price from a discounted one. Here's both directions, with examples retailers can use today.

Forward: price to sale price

To apply a discount, multiply the original price by the discount percentage and subtract. Discount amount = original price × discount % ÷ 100. A AED 200 item at 15% off saves AED 30, giving a AED 170 sale price. The free Discount Calculator shows the amount, the final price, and the saving instantly.

Backwards: sale price to original price

This is where mistakes happen. To recover the original price from a discounted one, divide by (1 − discount/100). For 20% off, divide the sale price by 0.8 — you do not add 20% back.

Watch your margins

Discounts come straight off your contribution margin. A 20% discount on a product with a 40% margin wipes out half your profit on that sale. Before running a promotion, check what the discount does to profitability with the Profit Margin Calculator.

Keep promotions under control

  • Decide the maximum discount your margin can absorb.
  • Prefer time-boxed offers over permanent price cuts.
  • Track the net effect on revenue, not just units sold.

Use the free Discount Calculator | Try the Profit Margin Calculator

Keep reading

More from Pyalm

Jun 27, 2026

Free UAE-Ready Invoicing: How to Start Before You Commit to E-Invoicing Software

You can create compliant-looking UAE tax invoices for free today — and have a clear, low-cost path to full PINT AE e-invoicing when your phase arrives. Here's how to do both without overpaying.

Jun 26, 2026

Are You Ready for UAE E-Invoicing? Take the 2-Minute Check

The UAE e-invoicing mandate is phased and unforgiving. Use this free readiness checker to see where you stand — and exactly what to fix before your go-live date.

Jun 26, 2026

UAE E-Invoicing Pilot Phase (From 1 July 2026): How to Test Before You're Mandated

From 1 July 2026 the UAE opens a voluntary e-invoicing pilot. Running real invoices through the system before your mandatory date is the lowest-risk way to get ready — here's how the pilot works and how to make the most of it.

Jun 25, 2026

The Fastest UAE E-Invoicing Solution — Zero Extra Development Cost

Most UAE e-invoicing implementations take weeks and cost extra in connectors and customisation. Pyalm Books is the exception: PINT AE compliance, Peppol transmission, FTA integration, and UAE VAT — all included, live in days.

Jun 25, 2026

5 Signs Your Business Has Outgrown Spreadsheets and Free Tools

Free invoice generators and spreadsheets get you started. Here are five signs it's time to move to proper accounting software — before UAE e-invoicing makes it mandatory.

Jun 24, 2026

White-Label E-Invoicing for UAE Accounting Firms: Power Your Clients with Pyalm Books

UAE e-invoicing compliance is now a service opportunity. Accounting firms, VAT consultancies, and software resellers can offer branded e-invoicing to their clients — without building software — through Pyalm Books.

Get UAE VAT & E-Invoicing Ready

Pyalm Books handles VAT, PINT AE e-invoices, and FTA returns for Dubai businesses — no extra development cost.

Log in to Pyalm Books Learn about Pyalm Books