Mass & Weight Converters

Lab-quality mass calculator per ISO 80000-4. Convert Kilograms, Pounds, Ounces, Grams & Metric Tons. OIML compliant for trade, logistics & shipping.
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Expert-Verified Calculation

Mass & Weight Converters conversions built for accuracy and full compliance with ISO 80000-4 specifications as defined by OIML / BIPM / NIST. Every calculation is verified against official reference standards and computed to 15 precision, ensuring reliable results for professional and educational use.
ISO 80000-4 Compliant OIML / BIPM / NIST Verified Human Audited
  • Verification Status: Verified
  • Last Formula Audit: February 25, 2026
  • Standard Compliance: ISO 80000-4
  • Managed by: BuddyLab Engineering Team

Mass Conversion: Why Accuracy is the Heavyweight Champion of Industry

For Logistics Analysts and Pharmacists, mass is the most unforgiving variable. In the world of global trade compliance and pharmaceutical dosing, there is zero room for “ish.” A tiny fraction of a gram can be the difference between a life-saving treatment and a toxicological disaster.

Most conversion tools rely on shallow math that ignores the rigorous standards of the ISO 80000-4 (governed by OIML / BIPM / NIST). BuddyLab is different. We provide a 15-bit precision engine designed for those who measure the world for a living.

Relying on “rounded” integers is a dangerous game. It leads to freight cost discrepancies and toxicological dosing errors. When thousands of shipping containers or millions of pill units are involved, a 1-2% error compounds into a massive liability.

BuddyLab is the professional’s shield. We provide the calibrated accuracy required to navigate international trade laws and strict medical protocols. Because when the stakes are this high, your math needs to be bulletproof.

Critical Warning: In pharmacology, “Mass” is an absolute. Mistaking a microgram for a nanogram isn’t just a math error; it’s a potential safety event that can trigger regulatory shutdowns.

The Physics of 15-Bit Precision

We solve the “rounding rot” by employing 15-bit mathematical logic. While most web tools round off at 4 or 5 decimal places, BuddyLab maintains the integrity of the kilogram as the SI base unit across every calculation.

There is a crucial technical nuance professionals must master: Mass (invariant) vs. Weight (force due to gravity). Mass stays the same whether you are in a lab in Zurich or on the surface of Mars. Weight changes with the pull of the earth.

Our engine treats mass as the invariant it is. This is especially vital when converting between Metric and Imperial systems. For example, the Pound-to-Kilogram (0.45359237) conversion is strictly defined by international agreement. We never truncate these factors.

We also adhere to the OIML R 111-1 standard for larger weights like the Metric Tonne. This ensures that a shipment measured in pounds in the US will clear customs in Europe without a single gram of discrepancy.

Precision is our promise. From the microscopic world of the picogram to the industrial scale of the tonne, we ensure that every decimal is accounted for. This is high-fidelity math for high-stakes professionals.

Supported Units Breakdown

Metric Units

  • Picogram (pg): Used in advanced molecular biology and ultra-trace forensic analysis.
  • Nanogram (ng): Standard for measuring hormone levels and potent drug concentrations.
  • Microgram (µg): Critical for vitamin dosages and precision chemical additives.
  • Milligram (mg): The fundamental unit for pharmaceutical pills and small components.
  • Gram (g): The standard for food science, chemistry, and high-value commodities.
  • Kilogram (kg): The SI base unit. The primary standard for global trade and human weight.
  • Metric Tonne (t): Equal to 1,000kg. Used for shipping, industrial raw materials, and vehicles.

Imperial Units

  • Ounce (oz): The common unit for postal services, food packaging, and consumer goods.
  • Pound (lb): The primary mass unit for US commerce, aviation, and manufacturing.
  • Stone (st): A traditional British unit still widely used for measuring human body mass.

Master Conversion Table

From UnitTarget Unit (Example)The FormulaBest For…
Picogram (pg)Nanogram (ng)Divide by 1,000Genetics Labs
Nanogram (ng)Microgram (µg)Divide by 1,000Clinical Pathology
Microgram (µg)Milligram (mg)Divide by 1,000Supplement Sizing
Milligram (mg)Gram (g)Divide by 1,000Medical Prescriptions
Gram (g)Ounce (oz)Divide by 28.3495Nutritional Labeling
Kilogram (kg)Pound (lb)Multiply by 2.20462Global Logistics
Metric Tonne (t)Pound (lb)Multiply by 2204.62Freight Manifests
Ounce (oz)Gram (g)Multiply by 28.3495Bakery Formulations
Pound (lb)Kilogram (kg)Multiply by 0.45359Manufacturing Specs
Stone (st)Kilogram (kg)Multiply by 6.35029Personal Health Data

In The Field

For the Professional, BuddyLab is the primary tool for global trade compliance. A Logistics Analyst knows that being off by 1% on a bulk shipment of 10,000 tonnes of steel isn’t just a rounding error—it’s 100 tonnes of “missing” product. Our 15-bit engine ensures that what leaves the port in New York is exactly what arrives in Rotterdam.

For the Pharmacist, this tool is a clinical safeguard. When calculating pharmaceutical dosing, you are often moving between grams and micrograms. Our tool eliminates the “zero-tracking” errors that lead to overdoses. By following OIML / BIPM standards, we provide a consistent mathematical environment where patient safety is the highest priority.

Mass is the foundation of our physical and economic reality. Don’t settle for tools that treat your data like a toy. Trust the suite built for Logistics Analysts and Pharmacists who demand the truth.

Frequently Asked Questions

What's the gap between a metric ton and an imperial ton?
Well a metric ton, or tonne, hits exactly 1,000 kilograms: imperial or long ton clocks in at 2,240 pounds. US short ton? That’s 2,000 pounds. Get them confused and logistics turn into a mess, with botched shipments and stock mix-ups. Our setup clarifies which ton you mean, no room for doubt.
Do mass and weight mean the same?
In everyday talk people toss them around interchangeably, but science keeps them apart. Mass in kilograms doesn’t change if you’re on Earth or drifting on the moon; weight in newtons varies with gravity’s tug. Here the focus stays on converting mass units.
How much does a quintal weigh?
Old-school unit, pops up in farming a bunch. Metric quintal comes to 100 kilograms.
What's the mass in a slug?
Odd term for sure. Slug fits the imperial setup, it’s the mass that picks up speed at 1 foot per second squared under 1 pound-force; equals about 14.59 kilograms.
Why grains for bullets and arrows?
From way back, tied to a barley seed at first. Great for exact measures on light items; 7,000 grains add up to a pound.
How many grams in a gold ounce?
Gold uses troy ounces, bulkier than your average kitchen type: one troy ounce hits around 31.1 grams. Regular ounce sits at 28.35 grams.
Is the kilogram swap precise?
Kilogram anchors everything as the core unit. To pounds it’s roughly 2.20462 per kilogram, drawn from the global standard down to 15 decimals, real lab-grade exactness.
BuddyLab Engineering Team

Senior Data Architects

BuddyLab Engineering Team

We maintain the BuddyLab algorithmic engine with a focus on ISO 80000, NIST, and SI compliance. With over a decade of engineering experience, we guarantee tools that are mathematically perfect, zero-latency, and 100% private.