Online calculators.

Age is shown as completed calendar years and months, followed by remaining days. End-of-month anniversaries use the final valid day of the month. A 29 February birthday is treated as 28 February in a non-leap year for this calculation.

Dates are compared as calendar dates, so daylight-saving clock changes do not add or remove a day. Supported dates: 1900–2100.

Elapsed days subtracts the start date from the end date: today to tomorrow is 1 day. Including both dates adds 1: today to tomorrow is 2 days. The weeks figure is complete groups of seven days, not working weeks. Weekends and holidays are included.

New quantity = original quantity × wanted servings ÷ original servings. Enter each ingredient in turn; the output stays in the same unit. Fractions such as 1/2 and 1 1/2 are supported. Seasoning, pan size and cooking time may need a separate adjustment.

Use the Unit converter’s Cooking volume category to change between named cup and spoon measures. This scaler does not convert cups to grams.

Choose a quantity, then the input and output units. Temperature uses an offset as well as a scale factor. Temperatures below absolute zero are rejected. kB/MB/GB use powers of 1000; KiB/MiB/GiB use powers of 1024.

Measurement reference: NIST SI conversion factors ↗. Values are displayed to 12 significant digits.

Cooking volume labels distinguish metric and US measures. A metric cup here is 250 mL, a metric tablespoon is 15 mL and a metric teaspoon is 5 mL. Check your recipe’s measuring system. Volume cannot be converted to ingredient weight without a density.

More: NIST culinary measurement tips ↗.

Percentage of a value: X × Y ÷ 100. Percentage proportion: X ÷ Y × 100, where Y cannot be zero. Percentage change: (new − original) ÷ original × 100; use a positive original value.

Each discount is applied in sequence, then optional tax is added to the discounted price. For example, 20% followed by 10% is a 28% combined discount. Prices are rounded to two decimal places at each stage. Savings are measured before added tax; shipping and other charges are not included.

The tip is calculated on the entered bill amount, including any tax already in that amount. The bill and tip are rounded to two decimal places, then split into equal shares. If the total cannot divide evenly, a few people pay one cent or paise more, so all shares add up exactly.

Remaining target = target minus money already saved. Divide it by the number of months to find the monthly amount. The suggested payment rounds up to two decimal places; the final payment is adjusted to reach the target exactly. Very small targets may be reached earlier.

This is a simple savings plan. It assumes no interest, returns, fees or inflation. Currency selection only labels amounts; it does not convert exchange rates.

This estimate uses a fixed interest rate, monthly reducing-balance interest, and payments at the end of each month. Monthly payment = P × r ÷ [1 − (1 + r)⁻ⁿ], where P is the amount, r is the annual interest percentage entered ÷ 1200, and n is the number of months. At 0% interest, payment = P ÷ n.

Enter the nominal interest rate. Fees, insurance, taxes, rate changes and lender-specific rounding are excluded. This is a planning estimate, not a loan quote. Compare the lender’s total costs as well as the monthly payment. CFPB loan-comparison guidance ↗.

IPv4 only. /31 uses both addresses for a point-to-point link; /32 represents one host route. Address counts describe the block, not permission to use reserved or public addresses.

Reference: IETF RFC 3021 ↗

Supports +, −, *, /, ^, !, parentheses, pi, e, sin, cos, tan, asin, acos, atan, sqrt, abs, ln, log, exp, floor and ceil. Log means base 10; ln means natural logarithm. Factorials accept integers 0–170.

Powers associate right to left: 2^3^2 = 512. Powers precede a leading minus: -2^2 = -4. Use (-2)^2 for 4. Results use real numbers and are rounded to 12 significant digits. Very small floating-point differences can occur.

V = I × R and P = V × I. Enter two known positive quantities; the other values follow from these equations. This tool models an ideal resistive DC load, without AC impedance or power factor.

Formula reference: OpenStax · Electric power ↗

Whole-number conversion stays exact for the supported input length. Hexadecimal accepts A–F in either case. Negative values are shown with a minus sign; this is not a two’s-complement converter.