{"uid":"cap_uwglvkTSxzPM1q9PUGV_F","slug":"roman-numeral-converter-94f48f47","name":"Roman Numeral Converter","description":"Convert 1-3999 to Roman numerals or read Roman numerals as numbers, strict or lenient (IIII, IC), additive style option.","url":"https://number-words.x402tookit.com/roman-numeral?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["value"],"properties":{"mode":{"enum":["strict","lenient"],"type":"string","description":"Reading Roman: strict (default; only standard forms) or lenient (also IIII, VIIII, IC, XM)"},"style":{"enum":["standard","additive"],"type":"string","description":"Writing Roman: standard (default, IV IX XL XC CD CM) or additive (IIII, VIIII, XXXX)"},"value":{"type":"string","description":"Digits 1 to 3999 (becomes Roman) or Roman letters such as MCMXCIV (becomes a number)"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"asOf":{"type":["null","string"]},"input":{"type":["null","string"]},"roman":{"type":["null","string"]},"style":{"type":["null","string"]},"number":{"type":["null","number"]},"source":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"summary":{"type":["null","string"]},"verdict":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"direction":{"type":["null","string"]},"disclaimer":{"type":["null","string"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}}}}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","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":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_VYZrsW75DsOPkBQGclFHk","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Converts integers (1–3999) to Roman numerals or parses Roman numeral strings back to integers, with strict/lenient reading and standard/additive writing styles.","exampleAgentPrompt":"Convert 1994 to a Roman numeral using standard style, and also tell me what number XLII represents — use strict reading mode.","exampleUseCases":[{"title":"Year displayed as Roman numerals","prompt":"What is the year 2024 written as a Roman numeral? Use standard style please."},{"title":"Decode Roman numeral on an old document","prompt":"I found 'MCMXCIX' on an old building — what year does that correspond to? Use strict reading mode."},{"title":"Validate lenient Roman numeral forms","prompt":"Parse 'IIII' as a number using lenient mode — I want to know if it's a valid Roman numeral and what value it represents."}],"resultDescription":"Returns the converted value (Roman numeral string or integer), the direction of conversion, the style and mode used, a human-readable summary, and optionally a list of reasons or warnings about the input form.","failureModes":["Input integer out of range (below 1 or above 3999) — returns error or null","Invalid Roman numeral characters in input — returns error or empty result in strict mode","Strict mode rejection of non-standard forms like IIII or IC — result with verdict and reasons","Missing required 'value' query parameter — returns validation error","Ambiguous input that could be either digits or Roman letters — may be misinterpreted"],"whenToPreferThis":"Use this endpoint when you need bidirectional conversion between Arabic integers (1–3999) and Roman numerals, especially when you need control over parsing strictness (allowing archaic forms like IIII) or writing style (additive vs. subtractive). Prefer it over manual lookup tables or general-purpose LLM generation when correctness and structured output (with reasons and verdict) matter.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-30T00:30:42.468Z","isFirstParty":false,"canonicalSlug":"roman-numeral-converter-94f48f47"}