PetexSpace
Length converterConvert millimetres, centimetres, metres, kilometres, inches, feet, yards, miles, and nautical miles.Weight converterConvert weight and mass between milligrams, grams, kilograms, tonnes, ounces, pounds, and stone, with the selected units shown together for comparison.Temperature converterConvert temperatures between Celsius, Fahrenheit, and Kelvin with absolute-zero validation.Area converterConvert square units, hectares, acres, and square miles.Volume converterConvert metric volume, US cooking and liquid units, and imperial gallons.Speed converterConvert metres per second, kilometres per hour, miles per hour, knots, and feet per second.Data unit converterConvert bits, bytes, KB through TB, and KiB through TiB with clear decimal and binary definitions.Age calculatorCalculate years, months, days, and total elapsed days from a date of birth to a chosen date.Date difference calculatorCalculate the difference between two calendar dates as total days, complete weeks, and remaining days, including dates entered in either order.Time duration calculatorFind hours and minutes between two clock times, including an optional next-day end time.Percentage calculatorFind a share percentage, a percentage of a value, or the percentage change between two values.Aspect ratio calculatorSimplify a width and height to their aspect ratio, then calculate matching dimensions from a new width or height for images, video, and layouts.Time-zone overlap calculatorCompare two working-hour windows on a chosen date, see their overlap in each time zone, and account for the daylight-saving offsets in effect that day.

Convert units and calculate everyday values

Use focused online calculators for unit conversions, dates, time, percentages, aspect ratios, data sizes, and working-hour overlap across time zones.

Clear calculations without setup

Choose a focused calculator, enter the known values, and review the result immediately. No account is required.

Frequently asked questions

How should I use the results?

The calculators use defined conversion factors or explicit formulas and are suitable for common reference, comparison, and planning. Accuracy still depends on the meaning and quality of the input. Rounded measurements, estimated dates, regional conventions, measurement uncertainty, and omitted real-world variables can matter more than additional decimal places. Read the limitation shown for the selected calculator and keep enough precision during intermediate steps. A mathematically correct result is not automatically a complete professional assessment, especially when regulations, tolerances, taxes, clinical context, or safety margins are involved.

Which calculator should I choose?

Choose the calculator by identifying the quantity, relationship, or calendar question you need to solve. Unit converters handle measurements only when the source and target units describe the same type of quantity. Date and time tools follow calendar or clock rules, while percentage and aspect-ratio tools require the correct base values. Read the labels, limitations, rounding behavior, and examples on the selected page, then check whether specialist rules apply to your medical, legal, financial, engineering, or regulated use case.

What should I check before using the result?

Confirm every input value, unit, sign, date, time zone, and selected mode before relying on the result. Check whether a percentage question asks for a share, a value, or a change, and whether a duration is allowed to cross midnight. For storage, distinguish decimal units based on 1000 from binary units based on 1024. For calendar results, consider leap days, month lengths, daylight-saving transitions, and local rules. For legal, medical, financial, engineering, or safety decisions, verify the calculation using the specialist method and definitions that apply to the real situation.

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