Chemical Name Calculator — IUPAC Binary Compound Naming
Select two elements and their subscripts to get the IUPAC systematic name, compound type (ionic or covalent), chemical formula, and molar mass for any binary compound.
First element
Second element
How does this calculator work?
Ionic naming: [Metal][Roman numeral if variable valence] [nonmetal]-ide — e.g., FeCl₃ = Iron(III) chloride. Covalent naming: [Greek prefix + element] [Greek prefix + element]-ide — e.g., N₂O₄ = Dinitrogen tetroxide. Oxidation state is inferred from charge balance. Molar mass is computed from atomic masses.
Formula
How this is calculated
IUPAC nomenclature for binary compounds follows two different rule sets depending on whether the compound is ionic (metal cation + nonmetal anion) or covalent/molecular (nonmetal + nonmetal).
For binary ionic compounds, the metal is named first (with a Roman numeral in parentheses if it has variable oxidation states — e.g., Iron(II) chloride vs. Iron(III) chloride), followed by the anion name, which uses the element's root with the suffix "-ide" (oxide, chloride, sulfide, bromide, iodide, fluoride, phosphide, nitride, carbide, hydride). The oxidation state of the metal is inferred from charge balance: total cation charge + total anion charge = 0. For main-group metals with fixed oxidation states (Na⁺, K⁺, Ca²⁺, Mg²⁺, Al³⁺), no Roman numeral is added.
For binary molecular (covalent) compounds — two nonmetals — Greek number prefixes (mono-, di-, tri-, tetra-, etc.) indicate the number of each atom. The first element omits the "mono-" prefix; the second always includes it. Vowel elision applies when a prefix ending in a vowel precedes a stem starting with a vowel (e.g., "mono" + "oxide" → "monoxide", "tetra" + "oxide" → "tetroxide"). This tool handles simple binary systems; polyatomic ions, coordination compounds, organic nomenclature, and acids are beyond its scope.
Frequently asked questions
Look at the two elements. If the first is a metal and the second is a nonmetal, it is ionic — name the metal, then the nonmetal with "-ide". If both are nonmetals, it is covalent — use Greek prefixes before each element name and add "-ide" to the second. For example: NaCl = Sodium chloride (ionic); CO₂ = Carbon dioxide (covalent, di- prefix on oxide, mono- omitted for first element).
Iron (and most transition metals) can form cations with different positive charges. Iron(II) means Fe²⁺ (the older name "ferrous"), and Iron(III) means Fe³⁺ (the older name "ferric"). The Roman numeral tells you the exact oxidation state, which is essential to writing the correct formula. Without it, you would not know whether to write FeCl₂ (Iron(II) chloride) or FeCl₃ (Iron(III) chloride).
Ionic compounds form when a metal transfers electrons to a nonmetal, creating oppositely charged ions held together by electrostatic attraction (e.g., NaCl: Na⁺ and Cl⁻). Covalent compounds form when two nonmetals share electrons in covalent bonds (e.g., CO₂: C shares two double bonds with two O atoms). Ionic compounds typically have higher melting points and conduct electricity when dissolved in water; covalent compounds generally have lower melting points and many are gases or liquids at room temperature.
TG we-Calculate Editorial Team. (2026). Chemical Name Calculator — IUPAC Binary Compound Naming [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/chemical-name-calculator
TG we-Calculate Editorial Team. "Chemical Name Calculator — IUPAC Binary Compound Naming." TG we-Calculate. 2026. https://we-calculate.com/calculator/chemical-name-calculator.
TG we-Calculate Editorial Team, "Chemical Name Calculator — IUPAC Binary Compound Naming," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/chemical-name-calculator
@misc{wecalculate_chemical_name_calculator, title = {Chemical Name Calculator — IUPAC Binary Compound Naming}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/chemical-name-calculator}}, year = {2026}, note = {TG we-Calculate} }
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