Sources
- CSGB / Asgari Ücret Tespit Komisyonu (2026 brüt/net)
- GİB gelir vergisi tarifesi 2026
- EPDK mesken elektrik kademeli tarife (yaklaşık)
- BOTAŞ / dağıtım şirketleri doğalgaz (yaklaşık)
- Hazine ve Maliye — kıdem tazminatı tavanı 1. dönem 2026
Discount Calculation Guide
Find savings, the final payable campaign price and the trap of adding discount rates.
Single-percentage discount
Multiply list price by the rate for savings, then subtract from list price. Convert 25% to 0.25 and watch store rounding rules.
Why stacked rates do not add
A 20% reduction followed by 10% applies the second rate to the remainder. The combined reduction is 28%, not 30%.
Reverse price and reference tricks
Divide sale price by one minus the rate to recover an original. Question whether the “was” price was recently real.
VAT, coupons and basket rules
Consumer tags are often VAT-inclusive. Thresholds, category exclusions, coupon caps and shipping can erase headline savings.
Multiple coupons and points
Stacking rules vary. A cap may cut the effective percentage. Read “cannot be combined” clauses before checkout.
True savings check
Savings equal a realistic reference minus amount paid minus mandatory extras. Compare unit prices across sellers. The tool is informational.
Cash versus instalment pricing
A discounted cash price is not the same as an instalment campaign. Losing a cash discount can cost more than “zero interest” marketing suggests. Compare cash total and instalment total on separate lines.
Unit price after packaging
Multipacks can look cheaper per package while rising per unit. Convert to price per litre, kilogram or piece before calling a deal real savings.
Practical tips
- Convert percent correctly.
- Apply rates sequentially.
- Check coupon caps and exclusions.
- Add shipping to the final price.
- Challenge inflated “was” prices.
- Compare cash and instalment totals separately.
- Convert multipacks to unit prices.
FAQ
Is 20% plus 10% equal to 30%?
No. Sequential application gives 28%.
How is original price recovered?
Divide final price by one minus the discount rate.
Why is my coupon weaker than expected?
Basket thresholds, exclusions or a maximum discount may apply.
Can two coupons stack?
Only if campaign rules allow it.
Is the calculator binding at checkout?
No. Till rules and fees prevail.
Are instalment deals equal to cash discounts?
Often not. Lost cash discounts or term costs can raise the true total.
Why check unit price?
Package deals can hide a higher price per unit.