Standard Data APIs.
Reference data APIs serve the lists everyone copies into a constants file and never updates — countries, currencies, languages, timezones, ISO codes. Query them instead of shipping a stale table that breaks the day a code changes.
Also called reference data APIs, lookup APIs or ISO code APIs51 services in this categoryStandard Data APIs
51 servicesGenerate iCal API
Create .ics calendar invites in your app. Send event details as JSON & get an iCal file that works in Google Calendar, Outlook & Apple Calendar. Free tier.
ApyHubVerifiedHosted on ApyHubSearch Books & Authors API
Search authors and books, fetch book details by ID, and find similar titles. Use it for catalog search, filters, and book recommendations.
Convert Timezone and Meeting Planner API
Convert local datetimes across IANA time zones with DST-aware offsets, or plan meetings across zones. Returns source, UTC, and target times.
Language Dictionary API
Get every ISO 639-1 language as JSON with its two-letter code, English name and native name, like de, German, Deutsch. Built for language pickers. Free tier.
ApyHubVerifiedHosted on ApyHubPublic Holidays API
Get the public holidays for a country and year as clean JSON with dates and names. Built for business-day math, scheduling, payroll and leave calendars.
ApyHubVerifiedHosted on ApyHubAdvanced Schedule Cron API
Compute upcoming fire times for a 5-field cron expression. Returns next_runs, a count, the timezone, and the reference time used, all in UTC.
Business Days Calculator API.
Add or subtract business days, count them between dates, or check if a date is a business day, using real holidays for US, UK, CA, AU, DE, FR and IN.
Working Day Calculator API
Count the working days between two dates for a country, with weekends and public holidays excluded. Get a JSON breakdown for payroll, SLAs and scheduling.
ApyHubVerifiedHosted on ApyHubConvert Date & Time Formats API
Convert ISO strings, unix epochs, or the current time into UTC, localized, and relative formats. Returns weekday, week number, and epoch values.
Foreign Exchange Rates API
Get exchange rate data for any base currency. Returns a success flag, numeric code, and the rate blocks used in pricing, billing, and reporting.
Advanced IBAN Validation API
Validate an IBAN from a single query parameter and get a success and code response. Built for payment flows and quick bank-detail checks.
Search US Address API
Search address matches from a text query, with optional country filtering and result limits. Built for autocomplete, lookup, and validation.
Dosvak LLCWhich Standard Data API do you need?
The question you arrived with, and the endpoint that answers it.