Salary Calculator
Estimate monthly and yearly take-home salary after deductions.
% of · % change · ratio
Percentage Calculator
Three modes in one tool: find a portion (X% of Y), find a rate (X is what % of Y), or calculate percentage change — with remainder, multiplier, and ratio shown automatically.
Step By Step
How to Use This Calculator
4 steps
- Choose a calculation mode from the three tabs: 'X% of Y' for finding a portion, 'X is what % of Y' for finding a rate, or '% Change X → Y' for finding a rise or fall.
- Enter the two values shown for that mode — both fields must be filled to see a result.
- Read the primary result (large number at the top) and the two detail tiles below for extra context such as remainder, ratio, or multiplier.
- Switch modes without losing confidence — the tab bar resets the fields automatically to avoid mixing values from a previous calculation.
Worked Example
Example: salary increment
Use this sample to sanity-check your inputs and understand what the final result represents.
- 1Mode: % Change X → Y
- 2Original value (X): 35,000
- 3New value (Y): 42,000
Final Result
+20% increase · Absolute change: +7,000 · Multiplier: ×1.2000
Methodology
Percentage formulas & references
This section explains the calculation logic, assumptions, and source material used to make the result more trustworthy and easier to verify.
Mode 1 — Portion: Result = Y × (X ÷ 100). Mode 2 — Rate: Result = (X ÷ Y) × 100. Mode 3 — Change: Result = ((Y − X) ÷ X) × 100; always divide by the original value X. Multiplier (Mode 3) = Y ÷ X; values above 1 indicate growth, below 1 indicate decline. References: ISO 80000-1 (quantities and units); OECD Glossary of Statistical Terms — Percentage Change.
Helpful tips
- 1% Change always uses the original value as the denominator. A 20% loss needs a 25% gain to recover — because the base is now smaller.
- 2To find VAT on a net price: enter the tax rate and net amount in '% of Y' mode; the result is the VAT amount to add.
- 3The multiplier tile (× n) is useful for compound growth — e.g. ×1.05 repeated 3 times = 1.05³ ≈ 15.8% total growth.
- 4Round invoice results to 2 decimal places; the detail tiles show up to 4 decimals for accuracy.
Frequently Asked Questions
What are the three percentage calculation modes?+
Mode 1 — 'X% of Y': finds the portion (e.g. 15% of 8,000 = 1,200). Mode 2 — 'X is what % of Y': finds the rate (e.g. 450 out of 3,000 = 15%). Mode 3 — '% Change X → Y': finds how much a value rose or fell relative to the original (e.g. 500 to 650 = +30%). All three are standard arithmetic identities used in finance, retail, and statistics.
What is the formula for each mode?+
Mode 1: Result = Y × (X ÷ 100). Mode 2: Result = (X ÷ Y) × 100. Mode 3: Result = ((Y − X) ÷ X) × 100. For percentage change, the original value X is always the denominator — using the new value instead is a common mistake that gives the wrong direction and magnitude.
Why does percentage change give a different result depending on direction?+
Because the denominator changes. Going from 100 to 80 is a −20% change (20 ÷ 100). Going back from 80 to 100 is a +25% change (20 ÷ 80). This asymmetry is mathematically correct and is why a 20% loss requires a 25% gain to break even. Always use the starting value as the base.
What does the 'Remainder' detail tile show?+
In Mode 1 (X% of Y), the remainder is Y minus the calculated portion. For example, if 15% of 8,000 is 1,200, the remainder is 6,800 — the part of Y not represented by X%. This is useful when splitting a budget or calculating what's left after a discount or commission.
What does the 'Multiplier' tile in % Change mode mean?+
The multiplier is the new value divided by the original value (Y ÷ X). A multiplier of 1.30 means the value grew to 130% of its original — equivalent to a +30% increase. A multiplier of 0.85 means it dropped to 85% — a −15% decrease. This form is common in financial modelling and compound growth calculations.
Can I calculate VAT or discount using this tool?+
Yes, with Mode 1. To find VAT on a net price, enter the tax rate and the net amount — the result is the VAT amount; add it to the net for the gross price. For a discount, enter the discount rate and the original price — the result is the saving; subtract it for the sale price. For more detail, use the dedicated VAT or Discount Calculator on this site.