Calculators that understand plain language
VAT, discounts, profit, ROAS, Thai land units, air-con size, age — every formula has a source
Money· Percentages, discounts, VAT and returns
- Percentage CalculatorX% of a number, percent change, add or subtract a percentage
- Discount CalculatorPrice after a % or fixed discount, including stacked discounts
- Thai VAT Calculator (7%)Add VAT or extract it from a VAT-inclusive price, rounded per the Revenue Department
- ROI CalculatorInvested this, got that back: what percent return?
- Loan Payment CalculatorMonthly instalment and total interest, flat rate or reducing balance
- Compound Interest CalculatorStart with this much at this rate: how much after a number of years?
- Hourly Wage and Overtime Pay Calculator (Thailand)Salary to hourly wage, overtime at 1.5×, holiday work at 1–3×
- Severance Pay CalculatorHow many days’ and baht of severance, by length of service (section 118)
- Thai Salary Income Tax CalculatorThai personal income tax for tax year 2569 (2026) from salary, bonus and allowances
- Electricity Bill CalculatorYour Thai home electricity bill at the new September 2569 rates, MEA and PEA
- Thai Annual Car Tax CalculatorYour annual vehicle tax by cc or weight, with up to 50% off for older cars
- Thai Net Salary CalculatorTake-home pay after withholding tax, social security and provident fund
Home· Tiles, air-conditioner size and room area
- Tile CalculatorHow many tiles and boxes to buy, including waste
- Air-Conditioner BTU CalculatorWhat BTU for this room, per EGAT’s table
- Area CalculatorRectangle, triangle, trapezoid, circle in m² and square wah
- Electricity Bill CalculatorYour Thai home electricity bill at the new September 2569 rates, MEA and PEA
Area· Rai, ngan, square wah and shapes
Business· Profit, margin, VAT, ROI and ROAS
- Thai VAT Calculator (7%)Add VAT or extract it from a VAT-inclusive price, rounded per the Revenue Department
- Profit, Margin & Markup CalculatorProfit, margin %, and selling price from a target margin or markup
- ROAS CalculatorAd revenue as a multiple of ad spend
- ROI CalculatorInvested this, got that back: what percent return?
- Hourly Wage and Overtime Pay Calculator (Thailand)Salary to hourly wage, overtime at 1.5×, holiday work at 1–3×
- Severance Pay CalculatorHow many days’ and baht of severance, by length of service (section 118)