Examples
Examples
Try the starting example
- Original lines: ID, original net $, original tax $
- A,100,20 B,200,10
- Credit lines: original ID, fraction of that original line %
- A,50 B,25
- Net credit by original line ($)
- A: 50.00; B: 50.00
- Tax credit by original line ($)
- A: 10.00; B: 2.50
- Total gross credit ($)
- $112.50
- Original gross less this credit ($)
- $217.50
Try another scenario
- Original lines: ID, original net $, original tax $
- A,100,20 B,200,10
- Credit lines: original ID, fraction of that original line %
- A,100 B,100
- Net credit by original line ($)
- A: 100.00; B: 200.00
- Tax credit by original line ($)
- A: 20.00; B: 10.00
- Total gross credit ($)
- $330.00
- Original gross less this credit ($)
- $0.00
Calculation method
Calculation method
Net credit by original line ($)
Round original net×credited fraction half-up to US cents.
Tax credit by original line ($)
Reverse the same fraction of original recorded tax, rather than applying a current rate.
Total gross credit ($)
Sum rounded net and tax credits.
Original gross less this credit ($)
Original gross total−this gross credit; prior credits must already be reflected in the inputs.
Symbols and units
- a
- Original lines: ID, original net $, original tax $
- b
- Credit lines: original ID, fraction of that original line %
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- A fractional reversal of recorded original line values. It does not create a legal credit note, select tax rates, infer entitlement or track credits that are absent from the supplied records.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
HMRC: tax fractions, invoice rounding and credit-note background; rules vary ↗
Background reading; this does not imply endorsement or independent review of SumFizz.