{"uid":"cap_G8OXSrSdOKRcZPvm41pwv","slug":"molar-mass-calculator-api-f65b1251","name":"Molar Mass Calculator API","description":"Molar mass API: compute the molecular weight of any chemical formula in g/mol — handles nested parentheses (Ca(OH)2, Fe2(SO4)3) and hydrates (CuSO4·5H2O). Returns the total, atom count, and a per-element breakdown with mass percentages. For chemistry, lab, pharma, and education agents.","url":"https://x402.forgemesh.io/molar-mass","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_Gw9_WpNJGuoJZ7ZyqwcYA","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":"Computes the molecular weight (g/mol) of any chemical formula, returning total molar mass, atom counts, and per-element mass breakdown","exampleAgentPrompt":"What's the molar mass of copper sulfate pentahydrate (CuSO4·5H2O)? I also want a breakdown of each element's percentage by mass.","exampleUseCases":null,"resultDescription":"Returns the total molar mass in g/mol, the total atom count in the formula, and a per-element breakdown including each element's symbol, count, individual atomic mass contribution, and percentage of total molecular weight.","failureModes":["Invalid or unrecognized chemical formula returns an error response","Malformed parentheses or unsupported formula notation may cause parsing failure","Unknown element symbols (e.g. typos) will result in an error","Empty or missing formula field returns validation error"],"whenToPreferThis":"Use this endpoint when you need fast, programmatic calculation of molecular weight for any chemical formula — especially when handling complex structures like nested parentheses (Ca(OH)2, Fe2(SO4)3) or hydrates (CuSO4·5H2O). Ideal for chemistry, pharma, lab automation, and education agents that need per-element mass composition alongside total molar mass.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-13T12:58:51.888Z","isFirstParty":false}