{"slug":"saylorinnovations-com-api-defi-apr-apy-e3ae0c","title":"Convert APR to APY or back at any compounding frequency, with daily rate, doubli","host":"saylorinnovations.com","method":"GET","resource":"https://saylorinnovations.com/api/defi/apr-apy","category":"market","description":"Convert APR to APY or back at any compounding frequency, with daily rate, doubling time and projected compounded versus simple earnings on a principal.","price_listed":0.01,"price_asked":0.01,"state":"answering","state_label":"Answering","checks_7d":1,"answered_7d":1,"latency_ms_median":283,"reported_calls_30d":0,"reported_payers_30d":0,"networks":["eip155:137","eip155:42161","eip155:8453","solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"method":"GET","queryParams":{"apr_percent":"12","compounds_per_year":"365","days":"180","principal":"5000"},"type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"method":{"enum":["GET"],"type":"string"},"queryParams":{"properties":{"apr_percent":{"description":"nominal APR in percent (or give apy_percent)","type":"string"},"compounds_per_year":{"description":"optional 1-100000 or continuous, default 365","type":"string"},"days":{"description":"optional projection days, default 365","type":"string"},"principal":{"description":"optional starting amount, default 1000","type":"string"}},"required":["apr_percent"],"type":"object"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"},"output":{"properties":{"example":{"properties":{"apr_percent":{"description":"Nominal annual rate without compounding, in percent","type":"number"},"apy_percent":{"description":"Effective annual rate including compounding, in percent","type":"number"},"balance_compounded":{"description":"Balance after the period with compounding at the APY","type":"number"},"balance_simple_apr":{"description":"Balance after the period earning simple interest at the APR","type":"number"},"compounding":{"description":"Compounding frequency used","type":"string"},"compounding_gain_percent_points":{"description":"APY minus APR in percentage points","type":"number"},"daily_rate_percent":{"description":"Equivalent daily compounded rate, in percent","type":"number"},"days":{"description":"Projection length in days","type":"number"},"doubling_time_days":{"description":"Days for the balance to double at this APY, null if the rate is not positive","type":["number","null"]},"earnings_compounded":{"description":"Earnings after the period with compounding","type":"number"},"earnings_simple_apr":{"description":"Earnings after the period with simple interest","type":"number"},"note":{"description":"Plain-language caveat about how to read and use the result","type":"string"},"principal":{"description":"Starting amount used","type":"number"},"source":{"description":"Where the data or formula comes from","type":"string"}},"required":["apr_percent","apy_percent"],"type":"object"},"type":{"const":"json","type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[{"day":"2026-10-20","reachable":true,"status":402,"valid_402":true,"asked_usdc":0.01,"price_match":true,"latency_ms":283,"error":null}],"description_full":"Convert APR to APY or back at any compounding frequency, with daily rate, doubling time and projected compounded versus simple earnings on a principal.","last_updated":"2026-10-20T14:45:32.833Z","schemes":["exact"]}