{"uid":"cap_WARwCQjXMsLvvxC6kHBPG","slug":"forgemesh-molar-mass-molecular-weight-api-222453b7","name":"ForgeMesh Molar Mass / Molecular Weight API","description":"Molar mass API: the molecular weight of any chemical formula (H2O, C6H12O6, Ca(OH)2, CuSO4·5H2O) in g/mol, with a per-element mass breakdown and mass percentages. Nested groups and hydrates supported.","url":"https://x402.forgemesh.io/molecular-weight","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"formula":{"type":"string","description":"chemical formula e.g. C6H12O6"}}},"responseSchema":{"type":"json","example":{"atom_count":3,"composition":[{"count":2,"element":"H","mass_percent":11.19},{"count":1,"element":"O","mass_percent":88.81}],"molar_mass_g_per_mol":18.015}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.003/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_OmQncft6gZrMKPbu504F0","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Calculates the molar mass of any chemical formula in g/mol, with per-element mass contributions and percentage breakdowns, supporting nested groups and hydrates.","exampleAgentPrompt":"What's the molar mass of copper sulfate pentahydrate (CuSO4·5H2O)? Also break down how much each element contributes by mass.","exampleUseCases":null,"resultDescription":"Returns the total molar mass in g/mol for the given chemical formula, along with a per-element breakdown showing each element's absolute mass contribution and its percentage of the total molecular weight. Supports nested parenthetical groups (e.g. Ca(OH)2) and hydrate dot notation (e.g. CuSO4·5H2O).","failureModes":["Invalid or unparseable chemical formula returns an error","Unsupported characters or isotope notation may not be handled","Unknown element symbols in the formula cause a parse failure","Missing required 'formula' field returns a validation error","Payment not completed or insufficient USDC balance results in 402 rejection"],"whenToPreferThis":"Choose this endpoint when you need a programmatic, per-element breakdown of molecular weight for arbitrary chemical formulas — especially formulas with nested groups like Ca(OH)2 or hydrates like CuSO4·5H2O — rather than a simple lookup table or calculator that only handles simple linear formulas.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T18:55:33.074Z","isFirstParty":false}