Weight Converter
Convert between kilograms, grams, pounds, ounces, and tons. Instant results, real-time stats.
⚖️ Converted Weight:
The conversion factors
Every unit is first converted to kilograms (the base), then to your target, using these fixed factors:
- Gram = 0.001 kg (exact, SI prefix)
- Kilogram = 1 kg - the SI base unit of mass
- Pound (lb) = 0.45359237 kg (exact)
- Ounce (oz) = 0.45359237 ÷ 16 = 0.028349523125 kg (exact)
- Tonne (t) = 1,000 kg (metric tonne)
Worked example: 100 lb = 100 × 0.45359237 = 45.359 kg. Because the pound and ounce factors are exact by definition, results carry no rounding error from the factors themselves - only from how many decimals you choose to read.
Where these numbers come from
The kilogram is the SI base unit of mass (defined since 2019 by fixing the Planck constant). The value 1 lb = exactly 0.45359237 kg is the international avoirdupois pound, agreed in 1959 by the US, UK and other nations and used by NIST and national metrology institutes - so it is a definition, not a measurement.
One honest limitation: “ton”
The “Ton (metric)” option here is the tonne = 1,000 kg. Do not confuse it with the US short ton (2,000 lb ≈ 907.18 kg) or the UK long ton (2,240 lb ≈ 1,016.05 kg), which this tool does not convert. Methodology last reviewed: October 2026. All maths runs client-side; nothing is uploaded.
How to Use Weight Converter
Follow these simple steps to get the best results.
Enter a weight and pick units
Type the value and choose the source and target units from grams, kilograms, tonnes, pounds and ounces; it converts live as you type, or press Convert to run it.
Read or swap the result
The converted weight appears in your target unit. Use Swap Units to reverse the direction, covering anything from kitchen grams to industrial tonnes.
Copy or download
Use Copy Result to save the value or Download for a text file, then Clear to reset. The pound is the exact 1959 international value and all maths runs in your browser.
Frequently Asked Questions
Everything you need to know about Weight Converter.
About the Weight Converter Tool
Switch between kilograms, pounds, ounces, and more with the ToolFlic Weight Converter. Whether you are shipping a package, following a fitness plan, or cooking an international recipe, our tool provides precise transformations between all major units of mass and weight.
Core Advantages
Avoid costly shipping errors and cooking mishaps by always having the correct weight conversions. Our tool is fast, free, and features a clean interface that makes it easy to switch between metric and imperial systems in just a few clicks.
Architecture & Security
By utilizing a centralized mass-conversion library, we ensure that every result fulfills the highest standards of mathematical accuracy. The entire transformation is performed locally in your browser for maximum speed and security.
Under the Hood: the Weight Converter explained properly
No marketing filler - just the mechanics, the trade-offs and the real limits, explained clearly.
How it actually works
Mass units (kilograms, grams, pounds and ounces) are each defined by their size in kilograms, the base, so a conversion multiplies into kilograms and divides out to the target, and the result also lists the same mass in the other common units at once.
What that means for your results
The pound is the exact 0.45359237-kilogram definition, so shipping and recipe figures stay consistent, and showing kilograms, grams and pounds together lets you sanity-check a value on one screen.
Where it falls short - honestly
It handles mass only, so stone, tonnes and troy ounces are not in the list, and it is a unit conversion rather than a scale: it cannot tell actual weight from dimensional weight, which couriers often bill on.
A real end-to-end workflow
Learn the pair that unlocks foreign recipes (one pound is about 454 grams), convert both actual and volumetric weight before choosing a courier, and keep one unit in a fitness log, using Length Converter for parcel dimensions and Unit Converter for wider needs.
In-Depth Guides Using This Tool
Tested workflows, exact sizes and limits - written step by step by the ToolFlic team.
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