Endpoint guide

Add to a timestamp

GET /v1/time/addOpenAPI YAML

Add days, hours, minutes, and seconds to a base timestamp. Modifiers may be negative.

What do I need to send?

Required / choose this first

Provide at least one modifier: days, hours, minutes, or seconds.

Optional

A base timestamp (unix, unix_ms, or iso) is optional; without one, the request time is used.

Rule: Use one base form and choose one target selector if you need a rendered timezone.

Name	Needed?	Use it for
`unix`	Choose one input	Base timestamp as Unix seconds. Defaults to current request time when omitted.
`unix_ms`	Choose one input	Base timestamp as Unix milliseconds.
`iso`	Choose one input	Base timestamp as ISO 8601.
`days`	Optional	Whole days to add. Negative subtracts.
`hours`	Optional	Hours to add. Negative subtracts.
`minutes`	Optional	Minutes to add. Negative subtracts.
`seconds`	Optional	Seconds to add. Negative subtracts.
`source_tz`	Conditional hint	Interpret a local iso= base as wall time in this IANA zone.
`source_ip`	Conditional hint	Interpret a local iso= base using this IP address timezone.
`source_lat`	Pair parameter	Latitude hint for local iso=. Pair with source_lon.
`source_lon`	Pair parameter	Longitude hint for local iso=. Pair with source_lat.
`source_offset`	Conditional hint	Interpret a local iso= base against a fixed UTC offset.
`tz`	Choose one target	Render the result in this IANA timezone.
`ip`	Choose one target	Render the result in the timezone of this IP address.
`lat`	Pair parameter	Target latitude. Pair with lon.
`lon`	Pair parameter	Target longitude. Pair with lat.
`offset`	Choose one target	Render the result against a fixed UTC offset (URL-encode + as %2B).
`utc`	Choose one target	Set true to render the target in UTC.
`format`	Optional	strftime pattern for an additional `formatted` field, e.g. %Y-%m-%d %H:%M:%S.
`sign`	Optional	Set true for a signed response.

Code samples

Copy a request in your preferred language and replace YOUR_TIMELOGIC_API_KEY with your direct API key.

curl "https://api.timelogicapi.com/v1/time/add?unix=1711300000&days=3&hours=2" \
  -H "Authorization: Bearer $TIMELOGIC_API_KEY"

Example response

{
  "unix": 1711566400,
  "unix_ms": 1711566400000,
  "utc": "2024-03-27T19:06:40Z",
  "iso_local": null,
  "rfc2822": "Wed, 27 Mar 2024 19:06:40 +0000",
  "human": "March 27, 2024, 7:06 PM UTC",
  "day_number": 4,
  "day_short": "Wed",
  "day_full": "Wednesday",
  "timezone": null
}

Additional endpoint notes

# Add 3 days and 2 hours to a Unix timestamp
https://api.timelogicapi.com/v1/time/add?unix=1711300000&days=3&hours=2

# Add 2h30m to an ISO timestamp
https://api.timelogicapi.com/v1/time/add?iso=2026-04-16T09:00:00Z&hours=2&minutes=30

# Subtract one day
https://api.timelogicapi.com/v1/time/add?unix=1711300000&days=-1

Provide at most one base form. With no base, the modifier is applied to the current request time.

Common errors

400 AMBIGUOUS_TARGET — multiple base forms supplied.
400 INVALID_PARAMETER — non-integer modifier values.

When to use this endpoint

Use Add to a timestamp when you need deterministic date math around an input moment. Common use cases include trial expiration, reminder scheduling, countdown targets, and generating future or past timestamps from a known base.

Request model

Pass one base timestamp (unix, unix_ms, or iso) or omit it to use the current request time. Then provide any combination of days, hours, minutes, and seconds; negative values subtract time.

Date math guidance

Use this endpoint when you want server-side consistency across clients. Store machine-readable values such as unix_ms for comparisons, then display the returned ISO or human string in the user's target context.