{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"unix-timestamp"},"result":{"entity_type":"calculator","id":"unix-timestamp","calculator_id":"unix-timestamp","canonical_url":"https://tttkmbb.com/time/unix-timestamp","name":"Unix Timestamp Converter","title":"Unix Timestamp Converter – Epoch Seconds or Milliseconds to ISO 8601 Date and Back","category":"time","category_name":"Time & Geography","tool_name":"convert_unix_timestamp","featured_mcp_tool":false,"description":"Converts a Unix timestamp (seconds or milliseconds since 1970-01-01T00:00:00Z, auto-detected) to a UTC and local date-time, or an ISO 8601 date-time (with optional time, offset or IANA zone) to epoch seconds and milliseconds, plus weekday, day of year and ISO week.","use_when":"You need to decode an epoch value from logs or an API, or produce the epoch seconds for a given calendar date and time.","do_not_use_when":"You need Julian Day numbers (use julian-date) or wall-clock conversion between two cities (use time-zone-converter).","inputs":[{"name":"timestamp","label":"Unix timestamp","type":"number","required":false,"min":-1000000000000000,"max":1000000000000000,"description":"Seconds since the Unix epoch; values with |timestamp| > 1e11 are read as milliseconds. Takes precedence over datetime when both are given.","example":1700000000},{"name":"datetime","label":"Date-time","type":"string","required":false,"description":"ISO 8601 date-time to convert instead of a timestamp: YYYY-MM-DD[THH:MM[:SS]] with optional Z or ±HH:MM offset; without an offset it is read in time_zone.","example":"2023-11-14T22:13:20Z"},{"name":"time_zone","label":"Time zone","type":"string","required":false,"default":"UTC","description":"IANA zone used to interpret a datetime without offset and to report the local date-time.","example":"UTC"}],"outputs":[{"name":"unix_seconds","label":"Unix seconds","type":"integer","unit":"s","decimals":0,"description":"Whole seconds since 1970-01-01T00:00:00Z (floored)."},{"name":"unix_milliseconds","label":"Unix milliseconds","type":"integer","unit":"ms","decimals":0,"description":"Milliseconds since the Unix epoch."},{"name":"iso_utc","label":"ISO 8601 (UTC)","type":"string","decimals":4,"description":"Instant in UTC, e.g. 2023-11-14T22:13:20Z (milliseconds shown only when non-zero)."},{"name":"utc_string","label":"HTTP date","type":"string","decimals":4,"description":"RFC 7231 / RFC 1123 form, e.g. Tue, 14 Nov 2023 22:13:20 GMT."},{"name":"local_datetime","label":"Local date-time","type":"string","decimals":4,"description":"Instant in time_zone with its UTC offset (ISO 8601)."},{"name":"utc_offset","label":"UTC offset","type":"string","decimals":4,"description":"Offset of time_zone at that instant (±HH:MM)."},{"name":"day_of_week","label":"Weekday (UTC)","type":"string","decimals":4,"description":"Day of the week of the UTC date."},{"name":"day_of_year","label":"Day of year (UTC)","type":"integer","decimals":4,"description":"Ordinal day of the UTC date, 1 January = 1."},{"name":"iso_week_date","label":"ISO week date","type":"string","decimals":4,"description":"UTC date in ISO 8601 week notation YYYY-Www-D."},{"name":"interpretation","label":"Input interpretation","type":"string","decimals":4,"description":"How the input was read (seconds, milliseconds, explicit offset or zone)."}],"input_schema":{"type":"object","properties":{"timestamp":{"description":"Seconds since the Unix epoch; values with |timestamp| > 1e11 are read as milliseconds. Takes precedence over datetime when both are given.","type":"number","minimum":-1000000000000000,"maximum":1000000000000000,"examples":[1700000000]},"datetime":{"description":"ISO 8601 date-time to convert instead of a timestamp: YYYY-MM-DD[THH:MM[:SS]] with optional Z or ±HH:MM offset; without an offset it is read in time_zone.","type":"string","examples":["2023-11-14T22:13:20Z"]},"time_zone":{"description":"IANA zone used to interpret a datetime without offset and to report the local date-time.","type":"string","default":"UTC","examples":["UTC"]}},"additionalProperties":false},"output_schema":{"type":"object","properties":{"unix_seconds":{"description":"Whole seconds since 1970-01-01T00:00:00Z (floored). Unit: s.","type":"integer","x-unit":"s"},"unix_milliseconds":{"description":"Milliseconds since the Unix epoch. Unit: ms.","type":"integer","x-unit":"ms"},"iso_utc":{"description":"Instant in UTC, e.g. 2023-11-14T22:13:20Z (milliseconds shown only when non-zero).","type":"string"},"utc_string":{"description":"RFC 7231 / RFC 1123 form, e.g. Tue, 14 Nov 2023 22:13:20 GMT.","type":"string"},"local_datetime":{"description":"Instant in time_zone with its UTC offset (ISO 8601).","type":"string"},"utc_offset":{"description":"Offset of time_zone at that instant (±HH:MM).","type":"string"},"day_of_week":{"description":"Day of the week of the UTC date.","type":"string"},"day_of_year":{"description":"Ordinal day of the UTC date, 1 January = 1.","type":"integer"},"iso_week_date":{"description":"UTC date in ISO 8601 week notation YYYY-Www-D.","type":"string"},"interpretation":{"description":"How the input was read (seconds, milliseconds, explicit offset or zone).","type":"string"}}},"formula":"unix_seconds = floor((instant − 1970-01-01T00:00:00Z) / 1 s); |timestamp| > 1e11 → milliseconds, else seconds; datetime without offset: instant = wall time − offset(time_zone)","method":"Unix time counts SI seconds ignoring leap seconds (POSIX definition), so every day has exactly 86,400 s. Supported instants: years 1 to 9999.","sources":[{"name":"IEEE Std 1003.1 (POSIX) – Seconds Since the Epoch","url":"https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_16","type":"standard","retrieved_at":"2026-09-24"},{"name":"Unix time (Wikipedia)","url":"https://en.wikipedia.org/wiki/Unix_time","type":"reference","retrieved_at":"2026-09-24"},{"name":"ISO 8601 – Date and time format (Wikipedia)","url":"https://en.wikipedia.org/wiki/ISO_8601","type":"reference","retrieved_at":"2026-09-24"}],"freshness":{"type":"static","max_age_seconds":null,"note":"Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output."},"examples":[{"name":"Timestamp 1700000000","inputs":{"timestamp":1700000000},"expected":{"unix_seconds":1700000000,"unix_milliseconds":1700000000000,"iso_utc":"2023-11-14T22:13:20Z","utc_string":"Tue, 14 Nov 2023 22:13:20 GMT","local_datetime":"2023-11-14T22:13:20+00:00","day_of_week":"Tuesday","day_of_year":318,"iso_week_date":"2023-W46-2"},"url":"https://tttkmbb.com/api/v1/calculate/unix-timestamp?timestamp=1700000000"},{"name":"2026-09-23 09:00 in Australia/Adelaide","inputs":{"datetime":"2026-09-23T09:00","time_zone":"Australia/Adelaide"},"expected":{"unix_seconds":1790119800,"iso_utc":"2026-09-22T23:30:00Z","local_datetime":"2026-09-23T09:00:00+09:30","utc_offset":"+09:30","day_of_week":"Tuesday","day_of_year":265},"url":"https://tttkmbb.com/api/v1/calculate/unix-timestamp?datetime=2026-09-23T09%3A00&time_zone=Australia%2FAdelaide"}],"faq":[{"q":"How do you tell seconds from milliseconds?","a":"Any absolute value above 1e11 is treated as milliseconds (1e11 s would be the year 5138), so 1700000000 is seconds and 1700000000000 is milliseconds."},{"q":"Are leap seconds counted?","a":"No. Unix time is defined without leap seconds; the 27 leap seconds inserted since 1972 are absorbed by repeating a second, so conversions here match POSIX and every standard library."}],"tags":["unix timestamp","epoch converter","epoch seconds","timestamp to date","date to timestamp","iso 8601"],"related":[{"calculator_id":"julian-date","reason":"Astronomical Julian Day for the same instant."},{"calculator_id":"time-zone-converter","reason":"Wall-clock time of the instant in another zone."},{"calculator_id":"date-difference","reason":"Days between two calendar dates."}],"links":{"html":"https://tttkmbb.com/time/unix-timestamp","markdown":"https://tttkmbb.com/time/unix-timestamp.md","json":"https://tttkmbb.com/time/unix-timestamp.json","api":"https://tttkmbb.com/api/v1/calculate/unix-timestamp","schema":"https://tttkmbb.com/api/v1/calculators/unix-timestamp","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-24"},"timestamp":"2026-09-24T01:45:31Z"}