Monoisotopic Formula Mass

Sum neutral monoisotopic mass from C/H/N/O/S/P atomic compositions.

Description

Monoisotopic formula mass sums fixed neutral-atom masses for C, H, N, O, S and P.

Monoisotopic formula mass sums fixed neutral-atom masses for C, H, N, O, S and P. It describes the specified isotope composition before adduct or charge conversion.^[1]

Sum neutral monoisotopic mass from C/H/N/O/S/P atomic compositions.

When to use Monoisotopic Formula Mass

Use this tool to sum neutral monoisotopic mass from C/H/N/O/S/P atomic compositions.

Prepare the measured profile, formula counts, upstream model outputs or caller-defined reference criteria requested. Keep paired entries aligned and units, sample basis and preprocessing consistent.

How to use Monoisotopic Formula Mass and understand its results

Prepare the measured profile, formula counts, upstream model outputs or caller-defined reference criteria requested. Keep paired entries aligned and units, sample basis and preprocessing consistent.
Enter carbon, hydrogen, nitrogen, oxygen, sulfur, phosphorus using the field table and calculation rules, then run the tool.
Read monoisotopicMassDa, atomCount. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
carbon	Carbon	number	Required
hydrogen	Hydrogen	number	Required
nitrogen	Nitrogen	number	Required
oxygen	Oxygen	number	Required
sulfur	Sulfur	number	Required
phosphorus	Phosphorus	number	Required

Enter nonnegative safe integer element counts with at least one atom. Use masses 12, 1.00782503223, 14.00307400443, 15.99491461957, 31.9720711744 and 30.97376199842 Da respectively. Return mass and total atom count.

massDa=Σ count_element×monoisotopicMass_element

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
monoisotopicMassDa	Monoisotopic mass da	number
atomCount	Atom count	number

json

{
  "input": {
    "carbon": 1,
    "hydrogen": 0,
    "nitrogen": 0,
    "oxygen": 0,
    "sulfur": 0,
    "phosphorus": 0
  },
  "output": {
    "monoisotopicMassDa": 12,
    "atomCount": 1
  }
}

Limitations and assumptions

No formula-string parsing, chemical validity or other elements are supported. Electron and adduct mass are not included.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Average Formula Mass: Sum molecular formula mass from caller-supplied average atomic weights. For a complementary task, use Adduct MZ: Calculate adduct ion m/z from neutral mass, injected mass shift, and charge.

References

Monoisotopic Formula Mass — tool.io

Similar or alternative tools

Average Formula Mass
Sum molecular formula mass from caller-supplied average atomic weights.
Adduct MZ
Calculate adduct ion m/z from neutral mass, injected mass shift, and charge.