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All 20 sections, every tool organised by topic.

💱
382 tools
Currency Insights
Explore currency calculation methods and practical examples...
💰
118 tools
Finance
Salary and tax, loan and mortgage repayments, savings growth...
❤️
61 tools
Health
BMI, BMR and kidney function; cycle, due-date and conception...
🔢
42 tools
Math
Percentage change versus percentage points, mean versus medi...
🔬
30 tools
Science
Molarity, dilution and pH for chemistry; force, energy and m...
🔥
26 tools
FIRE
Work out your FIRE number, your safe withdrawal rate and how...
📊
21 tools
Business
Liquidity, leverage, margin, cash-cycle and unit-economics c...
💼
19 tools
Work
Hourly rate, overtime and total compensation, plus statutory...
📈
18 tools
Statistics
Standard deviation, correlation and confidence intervals for...
18 tools
Sports
Pace, speed and race-time calculators for runners, cyclists...
📅
15 tools
Dates
Add days, weeks or months to a date, find the exact gap betw...
🍽️
13 tools
Food
Convert keg and bottle volumes into servings, butter between...
🔧
12 tools
Developer
Browser-side tools for formatting and inspecting the data de...
🔧
9 tools
Weather
Convert temperatures and work out wind chill, heat index, de...
🔄
6 tools
Converters
Convert kVA to amps, kW to amps for single- and three-phase...
✈️
5 tools
Travel
Work out fuel cost and consumption for a trip, journey time...
🏠
3 tools
Home
How big a heating or cooling system a room needs, how to mea...
🎓
2 tools
Education
Convert grades into a GPA on the standard 4.0 scale, or work...
🧾
2 tools
Tax
Income tax and VAT/GST calculators with a country selector c...
👗
1 tools
Fashion
Convert waist and inseam measurements into an actual jeans s...

Articles

All articles
A laptop on a wooden desk displaying a stock price line chart with volume bars

Capital gains tax brackets for 2025 and 2026, and how the 3.8% NIIT stacks on top

Long-term capital gains are taxed on a completely different scale from your paycheck, and where you land on it depends o...

An open amber prescription pill bottle filled with tablets, sitting on a dark wooden desk

HSA contribution limits for 2025 and 2026, and the eligibility rules that just changed too

The IRS raises the HSA contribution limit almost every year, and 2026 is no exception. What makes this year different is...

An overhead view of printed enrollment forms and a pen laid out on a plain wooden desk, with the edge of an open laptop visible

FSA contribution limits for 2026, and what actually carries over

The IRS raised the 2026 health FSA contribution limit by $100 and the maximum carryover by $20 — routine, incremental ch...

A plain brown window envelope with an official notice inside, lying on a desk next to a pen

The SAVE plan is winding down — what that means for the borrowers still on it

The SAVE plan spent nearly two years blocked in court, with millions of borrowers parked in an interest-free forbearance...

An older woman and a younger woman sitting close together at a table, both looking down at a printed document, with a coffee cup nearby

The 2026 gift tax annual exclusion, and how it fits with the lifetime exemption

Almost nobody who gives an ordinary gift ever owes gift tax, and the reason is two separate allowances stacking on top o...

A close-up overhead shot of an IRS 1040 tax form with a calculator and pen resting on top, on a dark desk

Social Security COLA 2026: what the 2.8% raise actually means

The Social Security Administration announced a 2.8% cost-of-living adjustment for 2026 on October 24, 2025. It is bigger...

A large white percentage sign standing on a wooden roof

What a rate change does to your mortgage payment

Central banks move rates in quarter points, and lenders pass them on in steps that look small on paper. Here is what eac...

A person at a desk holding a model house next to a calculator and paperwork

How much can I borrow, and what does a lender actually count?

The number a lender will give you is not your salary times four. It is a payment they think you can still afford if rate...

A small wooden model house beside a magnifying glass on a table

Fixed or variable: how to choose the way your rate is set

The choice is not a forecast about rates. It is a question about how much a known payment is worth to your household, an...

A man leans over a table reviewing papers

The enhanced ACA subsidies expired for 2026 — here is what changed in your premium

The enhanced ACA premium tax credit was always temporary, and it lapsed on schedule at the end of 2025. Here is exactly...

A closeup photo of a black car instrument cluster panel

The 2026 IRS standard mileage rate, and the mid-year raise nobody expected

The IRS set the 2026 mileage rates in December as usual — then changed the business and medical rates again in July, som...

A woman holding a man and a toddler by the hand

The 2026 adoption tax credit: the new maximum, and who the phase-out reaches

A 2025 law made part of the adoption tax credit refundable for the first time ever, worth up to $5,120 in 2026 even with...