Chemical Name Calculator
Convert any chemical formula to its IUPAC name and common name, or look up a formula from a compound's name.
🧪 What is a Chemical Name Calculator?
A chemical name calculator converts a chemical formula into its IUPAC systematic name and common name, or performs the reverse lookup to find a formula from a compound's name. It is an essential reference tool for chemistry students, lab technicians, educators, and anyone working with chemical compounds in research, industry, or education.
Chemical compounds have two types of names. The IUPAC systematic name is assigned by the International Union of Pure and Applied Chemistry and follows strict, universal rules. It is unambiguous and internationally recognised. The common name (also called a trivial name) is a traditional or historical name established through long usage: NaCl is "sodium chloride" by IUPAC rules, but most people call it "table salt". Both names are widely used and understanding the connection between them is a fundamental chemistry skill.
This calculator covers more than 200 common compounds spanning inorganic acids, salts, metal oxides, hydroxides, carbonates, sulfates, nitrates, and common organic molecules. For binary ionic compounds not in the database, it applies IUPAC rules automatically: it determines the metal oxidation state by charge balance and appends the appropriate Roman numeral for transition metals (iron, copper, chromium, manganese, cobalt, nickel, and others). For binary covalent compounds (two nonmetals), it applies Greek prefix naming: di, tri, tetra, penta, hexa.
The Name to Formula mode accepts both common names and IUPAC names. Typing "water", "oxidane", or "dihydrogen monoxide" all return H2O. Typing "baking soda" returns NaHCO3 (sodium hydrogen carbonate), and "Epsom salt" returns MgSO4 (magnesium sulfate). The molar mass is calculated automatically using IUPAC 2021 standard atomic weights and displayed in g/mol alongside each result.
📐 Naming Rules
📖 How to Use This Calculator
Steps
💡 Example Calculations
Example 1 - Table Salt (NaCl)
NaCl: sodium chloride, a binary ionic salt
Example 2 - Carbon Dioxide (CO2)
CO2: carbon dioxide, a binary covalent compound
Example 3 - Looking up Water by Name
Name to Formula: "water" returns H2O
Example 4 - Iron(III) Oxide (Fe2O3, Rust)
Fe2O3: iron(III) oxide, systematic naming with Roman numeral
❓ Frequently Asked Questions
🔗 Related Calculators
How do I find the IUPAC name of a chemical compound from its formula?
Enter the formula in the Formula to Name tab. The calculator first searches a database of 200+ common compounds, then applies IUPAC systematic rules for binary ionic compounds (e.g., iron with Roman numerals for oxidation state) and binary covalent compounds (Greek prefixes: mono, di, tri). For complex organics, a reference like IUPAC PubChem is needed.
What is the difference between an IUPAC name and a common name?
The IUPAC name is the systematic, internationally standardised name assigned by the International Union of Pure and Applied Chemistry, such as 'sodium chloride' for NaCl or 'oxidane' for H2O. A common name is a traditional or trivial name: 'table salt' for NaCl and 'water' for H2O. In lab settings and scientific literature, IUPAC names are preferred.
How do you name binary ionic compounds?
For binary ionic compounds (metal plus nonmetal): (1) Write the metal name unchanged. (2) For metals with fixed charge (Na, K, Ca, Mg, Al, Zn), no Roman numeral is needed. (3) For transition metals with variable charge (Fe, Cu, Co, Ni, Cr), calculate the oxidation state from charge balance and add it in Roman numerals: Fe2O3 contains Fe with +3 charge, so it is iron(III) oxide. (4) Change the nonmetal suffix to -ide: oxygen becomes oxide, chlorine becomes chloride.
How do you name binary covalent compounds?
Binary covalent compounds (two nonmetals) use Greek prefixes for atom counts: mono (1, omitted for the first element), di (2), tri (3), tetra (4), penta (5), hexa (6), hepta (7), octa (8). The first element uses its full name; the second uses its stem plus -ide. Examples: CO = carbon monoxide, CO2 = carbon dioxide, N2O5 = dinitrogen pentoxide, SF6 = sulfur hexafluoride. Drop the trailing vowel of the prefix when the stem starts with a vowel: penta + oxide = pentoxide.
What is the IUPAC name for water (H2O)?
The IUPAC systematic name for water (H2O) is 'oxidane'. This is the correct IUPAC PIN (preferred IUPAC name). However, 'water' is so universally established that IUPAC retains it as an acceptable name. In almost all practical and scientific contexts, 'water' is used. The systematic name 'dihydrogen monoxide' (from covalent naming rules) was historically used but is not the preferred IUPAC name.
What are the common names and formulas of everyday chemicals?
Table salt = NaCl (sodium chloride). Baking soda = NaHCO3 (sodium hydrogen carbonate). Bleach = NaClO (sodium hypochlorite). Epsom salt = MgSO4 (magnesium sulfate). Vinegar = CH3COOH (acetic acid). Ammonia = NH3 (azane). Quicklime = CaO (calcium oxide). Slaked lime = Ca(OH)2 (calcium hydroxide). Rust = Fe2O3 (iron(III) oxide).
How do you calculate the molar mass from a chemical formula?
The molar mass (Mr) is the sum of the standard atomic weights of all atoms in the formula: Mr = (number of each element) x (atomic weight). For H2SO4: Mr = 2(1.008) + 32.065 + 4(15.999) = 98.077 g/mol. Use IUPAC 2021 standard atomic weights: H=1.008, C=12.011, N=14.007, O=15.999, Na=22.990, S=32.065, Cl=35.453.
What is the difference between ionic and covalent compounds?
Ionic compounds form when a metal transfers electrons to a nonmetal, creating oppositely charged ions held together by electrostatic attraction. Examples: NaCl, CaCO3, MgSO4. Covalent compounds form when two nonmetals share electrons. Examples: CO2, H2O, NH3. Ionic compounds typically have higher melting points, dissolve in water to give conducting solutions, and name the metal first. Covalent compounds use Greek prefix naming.
What does the Roman numeral mean in an iron compound name?
The Roman numeral in parentheses after a transition metal name shows the metal's oxidation state (charge) in that compound. Iron can be Fe(+2) or Fe(+3). FeO is iron(II) oxide (iron is +2 because one oxygen is -2). Fe2O3 is iron(III) oxide (each Fe is +3 to balance three oxygens at -2 each, total -6, balanced by 2 x +3 = +6). Without the Roman numeral, the compound name would be ambiguous.
How do you name acids from their formulas?
Binary acids (H + nonmetal in aqueous solution): hydro + nonmetal stem + ic acid. HCl = hydrochloric acid, H2S = hydrosulfuric acid. Oxyacids (H + polyatomic ion with oxygen): the name depends on the -ate or -ite ion. H2SO4 = sulfuric acid (from sulfate SO4 2-), H2SO3 = sulfurous acid (from sulfite SO3 2-), HNO3 = nitric acid (from nitrate), HNO2 = nitrous acid (from nitrite), H3PO4 = phosphoric acid.
What is the chemical name for common household chemicals?
Hydrogen peroxide (H2O2): used as an antiseptic and bleaching agent. Sodium hypochlorite (NaClO): active ingredient in liquid bleach. Calcium carbonate (CaCO3): chalk, limestone, antacid tablets. Magnesium hydroxide (Mg(OH)2): milk of magnesia laxative. Aluminum oxide (Al2O3): found in sapphires and rubies. Carbon dioxide (CO2): fire extinguisher gas and carbonation in soft drinks. Acetic acid (CH3COOH): active component of vinegar.
What is the IUPAC name for ammonia (NH3)?
The IUPAC systematic name for ammonia is 'azane'. As a gas, NH3 is azane; as an aqueous solution it is ammonium hydroxide (NH4OH). The name 'ammonia' is the retained common name accepted by IUPAC for all practical purposes. Azane is used mainly in systematic nomenclature for naming organic nitrogen compounds as derivatives of NH3 (e.g., methylamine = methanamine).