Category · Unit Hub

Mass and Weight Converters

Every mass and weight unit in one place — 81 units, 6,480 conversions, grouped by family with a live calculator on the right. Use the popular shortcuts and matrix below for the most common pairs, or scroll the directory to find any unit and its full set of conversions.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Dr. Ashok Kumar K, Ph.D.
Mass and Weight category hub 81 units · 6,480 conversions Published Last reviewed Updated

Conversion matrix

The 10 most-used area units, every pair as a clickable link.

About area measurement

Mass and Weight is a fundamental geometric quantity equal to length squared. Every weight unit is derived from a corresponding length unit by squaring it — a square meter is the area of a square one meter on each side; an acre originated as the area a yoke of oxen could plow in a day, standardized in 1959 as exactly 4,046.8564224 square meters. In the International System of Units (SI), the square meter (m²) is the standard unit of area, with the hectare (10,000 m²) widely used for land measurement worldwide except in the United States, which uses the acre.

India's area landscape is uniquely diverse, with regional traditional units coexisting alongside metric and imperial standards. The bigha is the most prominent example — it has six distinct standardized values depending on the state (UP, Bihar, West Bengal, Gujarat, Rajasthan, Assam), all listed in our directory. Similarly, the cent (South India, 1/100 acre), guntha (Maharashtra/Karnataka, 1/40 acre), kanal and marla (Punjab) remain the primary units in regional real estate. Modern Indian land records typically cite both the traditional unit and its metric equivalent. The directory below covers all 73 area units this site supports, from the subatomic shed (10⁻⁵² m²) to the township (93.24 km²).

All area units

Tap any unit to expand its full list of outgoing conversions. Units are grouped by family.

Metric / SI · 18 units · 1344 conversions

Attogram (ag) — 79 conversions
Centigram (cg) — 79 conversions
Decigram (dg) — 79 conversions
Dekagram (dag) — 79 conversions
Exagram (Eg) — 79 conversions
Femtogram (fg) — 79 conversions
Gigagram (Gg) — 79 conversions
Gram (g) — 79 conversions
Hectogram (hg) — 79 conversions
Kilogram (kg) — 79 conversions
Metric Ton (t) — 79 conversions
Microgram (µg) — 79 conversions
Milligram (mg) — 79 conversions
Nanogram (ng) — 79 conversions
Petagram (Pg) — 32 conversions
Picogram (pg) — 48 conversions
Quintal (metric) (q) — 79 conversions
Teragram (Tg) — 79 conversions

Avoirdupois · 15 units · 1185 conversions

Clove (clove) — 79 conversions
Dram (avoirdupois) (dr) — 79 conversions
Grain (gr) — 79 conversions
Hundredweight (UK) (cwt) — 79 conversions
Hundredweight (US) (cwt) — 79 conversions
Kilopound (kip) (kip) — 79 conversions
Ounce (oz) — 79 conversions
Pound (lb) — 79 conversions
Quarter (UK) (qr) — 79 conversions
Quarter (US) (qr) — 79 conversions
Stone (UK) (st) — 79 conversions
Stone (US) (st) — 79 conversions
Ton (long, UK) (long tn) — 79 conversions
Ton (short, US) (sh tn) — 79 conversions
Wey (wey) — 79 conversions

Troy & Apothecary · 10 units · 790 conversions

Carat (metric) (ct) — 79 conversions
Dram (apothecary/troy) (dr ap) — 79 conversions
Mace (mace) — 79 conversions
Momme (mom) — 79 conversions
Pennyweight (dwt) — 79 conversions
Point (1/100 carat) (pt) — 79 conversions
Pound (troy/apothecary) (lb t) — 79 conversions
Scruple (apothecary) (s ap) — 79 conversions
Tael (tael) — 79 conversions
Troy Ounce (oz t) — 79 conversions

Indian / South Asian · 6 units · 474 conversions

Chittack (Chatank) (chittack) — 79 conversions
Masha (masha) — 79 conversions
Maund (Mann) (maund) — 79 conversions
Ratti (ratti) — 79 conversions
Seer (Ser) (seer) — 79 conversions
Tola (tola) — 79 conversions

Scientific / Atomic · 9 units · 711 conversions

Atomic Mass Unit (u) — 79 conversions
Carbon-12 Atom Mass (C-12) — 79 conversions
Deuteron Mass (md) — 79 conversions
Electron Mass (rest) (me) — 79 conversions
MeV/c2 (MeV/c²) — 79 conversions
Muon Mass (mµ) — 79 conversions
Neutron Mass (mn) — 79 conversions
Planck Mass (mP) — 79 conversions
Proton Mass (mp) — 79 conversions

Astronomical · 4 units · 316 conversions

Earth's Mass (M⊕) — 79 conversions
Jupiter Mass (MJ) — 79 conversions
Lunar Mass (Moon) (M☾) — 79 conversions
Sun's Mass (M☉) — 79 conversions

Biblical / Ancient · 14 units · 1106 conversions

Assarion (Biblical Roman) (assarion) — 79 conversions
Bekan (Biblical Hebrew) (bekah) — 79 conversions
Denarius (Biblical Roman) (denarius) — 79 conversions
Didrachma (Biblical Greek) (didrachma) — 79 conversions
Drachma (Biblical Greek) (drachma) — 79 conversions
Gerah (Biblical Hebrew) (gerah) — 79 conversions
Lepton (Biblical Roman) (lepton) — 79 conversions
Mina (Biblical Greek) (mina) — 79 conversions
Mina (Biblical Hebrew) (mina) — 79 conversions
Quadrans (Biblical Roman) (quadrans) — 79 conversions
Shekel (Biblical Hebrew) (shekel) — 79 conversions
Talent (Biblical Greek) (talent) — 79 conversions
Talent (Biblical Hebrew) (talent) — 79 conversions
Tetradrachma (Biblical Greek) (tetra) — 79 conversions

Force / Engineering · 5 units · 395 conversions

Kilogram-force square second/meter (hyl) — 79 conversions
Poundal (pdl) — 79 conversions
Slug (slug) — 79 conversions
Ton (assay) (UK) (AT) — 79 conversions
Ton (assay) (US) (AT) — 79 conversions

Frequently asked questions

What is the SI unit of area?

The square meter (m²). It is defined as the area of a square with sides of one meter. The hectare (10,000 m²) is also widely used for land measurement.

How many square feet are in one acre?

1 acre = 43,560 square feet exactly. This is defined by the 1959 International Yard and Pound Agreement, which set 1 foot = 0.3048 m and 1 acre = 4,840 sq yd.

What is one bigha in square feet?

It depends on the state. The pucca bigha (UP, Bihar) = 32,558 sq ft. The Bengal bigha = 14,400 sq ft. The Gujarat/Rajasthan bigha = 17,424 sq ft. Always confirm which regional definition applies to your land record.

How many square meters are in one hectare?

1 hectare = 10,000 square meters exactly = 100 ares = 2.47105 acres.

What is one cent of land?

1 cent = 1/100 acre = 40.4686 m² = 435.6 sq ft. The cent is the primary residential land unit in Kerala, Tamil Nadu, and Sri Lanka. In Bengal and Bangladesh, the same unit is called "decimal".

How precise are the conversions on this site?

All factors are stored exactly per BIPM/NIST/regional standards definitions. Indian regional units (bigha, katha) are flagged as approximate where their definitions vary by district. Displayed results are rounded only at the final step.

Source & reference

Definitions and conversion factors on this page follow the BIPM — International System of Units and the NIST guide to the SI. Imperial-to-metric conversions use the 1959 International Yard and Pound Agreement (1 yd = 0.9144 m exactly). Historical and ancient unit values follow standard reference works in metrology and archaeology.