Unit Converter — Length, Weight, Temperature, Area and More

What is a Unit Converter?

A Unit Converter (यूनिट कन्वर्टर) changes a measurement from one unit to another — centimetres to inches, kilograms to pounds, Celsius to Fahrenheit, square feet to square metres, litres to gallons, megabytes to gigabytes and so on. India uses the metric system officially, but everyday life is full of other units: height in feet and inches, screen sizes in inches, gold in tola, land in gaj and acres, recipes in cups, car specs in mph, and storage in GB and GiB. Converting accurately matters, whether you are buying land, filling a form, cooking, studying or comparing products.

This free converter covers eight categories and more than 80 units. Every unit is defined by its exact internationally agreed factor — for example 1 inch is exactly 2.54 cm and 1 pound exactly 0.45359237 kg — so results are as precise as the numbers you enter. It shows the formula used, and a table with your value in every unit of the category, which is handy when you are not sure which unit you need.

Key Features

• Eight categories — length, weight, temperature, area, volume, speed, time and data.
• Exact factors based on the international definitions of each unit.
• Indian units — tola, quintal and gaj (square yard).
• Temperature formulas for Celsius, Fahrenheit and Kelvin, with an absolute-zero check.
• Decimal and binary data units — KB, MB, GB, TB and KiB, MiB, GiB, TiB.
• Every unit at once in a table below the result.
• Swap button and shareable link.

How to Use It — Step by Step

1. Choose a category from the buttons at the top.
2. Enter the value to convert.
3. Pick the “from” unit under the value and the “to” unit under the result.
4. Read the result in the box and the full sentence below it, with the formula.
5. Check the table for the value in every other unit, or press swap to reverse the conversion.

Length Conversions

Height example: 5 ft 7 in = 5 × 30.48 + 7 × 2.54 = 170.18 cm. In the other direction, 170 cm ÷ 2.54 = 66.93 inches, which is 5 ft 6.93 in.

Weight (Mass) Conversions

The tola is still widely used for gold and silver in India and nearby countries. The standard tola is 180 grains, or about 11.66 grams — so 10 tola is about 116.64 g. Note that the gold carat used for purity (22K, 24K) is different from the gemstone carat used for weight.

Temperature Conversions

• °F = °C × 9/5 + 32 — so 37 °C = 98.6 °F and 100 °C = 212 °F.
• °C = (°F − 32) × 5/9 — so 98.6 °F = 37 °C.
• K = °C + 273.15 — so 25 °C = 298.15 K.

Temperature is the one category where you cannot simply multiply, because the scales have different zero points. −40 is the same in both Celsius and Fahrenheit. The converter refuses values below absolute zero (−273.15 °C), which cannot exist.

Area Conversions, Including Gaj

In north India, plot sizes are often quoted in gaj, which is a square yard. A 100 gaj plot is 900 sq ft or about 83.6 m². Traditional land units such as bigha, biswa, kanal, marla, cent and guntha differ between states and even districts, so they are not included — always confirm their local value with the land records office before a property deal.

Volume Conversions

• 1 US gallon = 3.785411784 L; 1 UK gallon = 4.54609 L.
• 1 US cup = 236.59 ml; 1 US tablespoon = 14.79 ml; 1 US teaspoon = 4.93 ml.
• 1 US fluid ounce = 29.57 ml; 1 cubic foot = 28.3168 L; 1 m³ = 1,000 L.

Recipes from the US use US cups and spoons; many UK and Australian recipes use metric cups (250 ml), so a “cup” is not always the same size.

Speed, Time and Data

• Speed: 1 km/h = 0.2778 m/s; 1 mph = 1.609344 km/h; 1 knot = 1.852 km/h. 100 km/h ≈ 62.14 mph.
• Time: the converter uses an average month of 30.44 days and an average year of 365.2425 days (the Gregorian average) for month and year conversions.
• Data: decimal units go up by 1,000 (1 GB = 1,000 MB), binary units by 1,024 (1 GiB = 1,024 MiB). Internet speeds are in bits: a 100 Mbps connection downloads at most about 12.5 megabytes per second.

Precision and Rounding

The converter calculates with full double-precision arithmetic and shows up to 10 significant digits, switching to scientific notation (for example 1.5e-7) for very large or very small results. Because the factors are exact definitions, the only rounding is in the final display. For practical work, round to a sensible number of digits: a room measured to the nearest centimetre does not need its area quoted to six decimal places, while a laboratory measurement might. When converting back and forth, start again from the original value rather than from an already-rounded result, so small rounding errors do not accumulate.

A Short History of Units

The metric system was created in France in the 1790s to replace hundreds of local units with a single decimal system. India adopted it officially in the late 1950s and completed the switch in the 1960s, which is why kilograms, metres and litres are used in trade today, while older units such as the tola, maund, seer and gaj survive in everyday speech and some markets. The United States still mainly uses US customary units, and the UK uses a mix of metric and imperial. In 1959 several countries agreed on exact metric definitions of the yard and pound, which is why the inch is exactly 2.54 cm.

Everyday Uses

• Converting your height and weight for forms, visas and fitness apps.
• Checking plot and flat sizes in sq ft, gaj, m² and acres.
• Gold and silver weights in tola and grams.
• Cooking with international recipes.
• Reading car, bike and aviation specifications in mph, knots and km/h.
• Understanding storage, file sizes and internet speed.
• Science and engineering homework.

Common Mistakes to Avoid

• Typing 5.7 for 5 ft 7 in — 5.7 feet is 5 ft 8.4 in. Convert feet and inches separately.
• Mixing US and UK volumes — gallons, pints and fluid ounces differ.
• Assuming a bigha is the same everywhere — it is not.
• Confusing bits and bytes — Mbps is megabits, MB/s is megabytes.
• Multiplying temperatures — use the formulas, not a single factor.

Tips and Troubleshooting

• A result shows “e” — that is scientific notation; 2.5e-7 means 0.00000025.
• Your unit is missing — find its value in a listed unit (for example a local land unit in square feet) and convert from there.
• Sharing — the link keeps the category, value and units.

Quick Glossary

• SI / metric system: the international system based on metres, kilograms and seconds.
• Imperial / US customary: systems using inches, feet, pounds and gallons.
• Gaj: square yard, used for plot sizes in India.
• Tola: traditional unit for precious metals, about 11.66 g.
• KiB, MiB, GiB: binary data units (powers of 1,024).

Why Use This Unit Converter?

It is precise, covers the units people in India and around the world actually use, explains each conversion and shows every unit at once. It is free, instant and keeps everything on your device.

Unit Converter — Key Facts

Frequently Asked Questions

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