SMILES Delimiter Validator

Check SMILES branch and atom-bracket balance; does not verify chemical valence.

Description

SMILES strings use parentheses for branches and brackets for atom expressions.

SMILES strings use parentheses for branches and brackets for atom expressions. Delimiter balance is only one structural-text check.^[1]

Check SMILES branch and atom-bracket balance; does not verify chemical valence.

When to use SMILES Delimiter Validator

Use this tool to check SMILES branch and atom-bracket balance; does not verify chemical valence.

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 SMILES Delimiter Validator 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 smiles using the field table and calculation rules, then run the tool.
Read delimitersBalanced, branchCount, bracketCount. 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
smiles	Smiles	string	Required

Paste text. Push opening delimiters, require matching closing types and count opened branches/brackets. On the first mismatch, return false with counts accumulated so far; otherwise report final balance. Empty text passes.

balanced=properly nested () and [] with empty final stack

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

Output field	Meaning	Value type
delimitersBalanced	Delimiters balanced	boolean
branchCount	Branch count	number
bracketCount	Bracket count	number

json

{
  "input": {
    "smiles": "C(=O)N[C@H](C)O"
  },
  "output": {
    "delimitersBalanced": true,
    "branchCount": 2,
    "bracketCount": 1
  }
}

Limitations and assumptions

Atoms, bonds, ring closures, stereochemistry and valence are not parsed. A balanced string is not necessarily valid SMILES.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Extremely large text inputs are rejected. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.

Alternative or Complementary methods

Use Inchikey Format Validator: Validate the syntactic InChIKey block lengths and separators. For a complementary task, use HMDB Accession Validator: Validate an HMDB accession against a caller-specified numeric width.

References

SMILES Delimiter Validator — tool.io

Similar or alternative tools

Inchikey Format Validator
Validate the syntactic InChIKey block lengths and separators.
HMDB Accession Validator
Validate an HMDB accession against a caller-specified numeric width.