Estimate overweight baggage fees.
Overweight baggage is charged in flat bands, not per kilogram, and that structure has a sharp consequence: one kilogram over the allowance costs exactly the same as eight kilograms over. There is no partial charge and no proportionality, which is why the amount to remove is often trivially small relative to the fee. Above 32 kg a second and much higher band applies, and above 32 kg most carriers refuse the bag entirely — that is an occupational health limit for baggage handlers rather than a pricing decision, so no fee will persuade them to accept it. Moving a couple of kilograms into hand luggage at the kerb is usually the whole solution.
Fee band
No fee at or below allowance; first band fee up to the threshold; second band fee above it
Weight to remove
Remove kg = actual weight - included allowance
Because carriers price overweight in flat bands to keep check-in simple and to deter the practice rather than monetise it proportionally. It also means the fee is entirely avoidable: shifting a laptop and a pair of shoes into your cabin bag frequently saves the whole charge.
Most airlines refuse the bag regardless of what you are willing to pay. The limit exists because a single handler lifts bags repeatedly in a confined hold, and 32 kg is a widely adopted occupational safety ceiling. You will be asked to repack into two bags at the counter.