ToolAssay

List the daylight-saving transitions for an IANA time zone over a date range

List the daylight-saving transitions for an IANA time zone over a date range: the exact instant of each shift, the offset before and after, and whether local clocks jump forward or back. Returns the current offset and DST state, and the next transition from a given instant. Zones without DST return an empty transition list rather than an error.

Answeringour last check, 2026-09-29
1 of 1checks answered this week
22 msmedian answer time
$0.05listed price per call
$0.05price it asked us

Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.

Endpoint

GET https://api.duoleads.com/v1/time/dst

CategoryEverything else
Provider hostapi.duoleads.com
Networkseip155:8453
Payment schemesexact
Self-reported calls, 30 days1 from 1 payers (the provider's figure, not ours)

Our checks, last 30 days

DayResultHTTPAskedTime
2026-09-29 valid payment request 402$0.05 22 ms

Example input (from the provider)

{
  "method": "GET",
  "queryParams": {
    "from": "2026-01-01",
    "years": "1",
    "zone": "Europe/Amsterdam"
  },
  "type": "http"
}

Promised output schema (from the provider)

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "input": {
      "additionalProperties": false,
      "properties": {
        "method": {
          "enum": [
            "GET"
          ],
          "type": "string"
        },
        "queryParams": {
          "properties": {
            "from": {
              "description": "Start of the range: RFC 3339 or YYYY-MM-DD. Default now.",
              "maxLength": 64,
              "type": "string"
            },
            "years": {
              "default": "2",
              "description": "Length of the range in years, 1-10. Default 2.",
              "maxLength": 64,
              "pattern": "^[+-]?\\d+$",
              "type": "string"
            },
            "zone": {
              "description": "IANA time zone id.",
              "maxLength": 64,
              "type": "string"
            }
          },
          "required": [
            "zone"
          ],
          "type": "object"
        },
        "type": {
          "const": "http",
          "type": "string"
        }
      },
      "required": [
        "type",
        "method"
      ],
      "type": "object"
    },
    "output": {
      "properties": {
        "example": {
          "properties": {
            "data": {
              "type": "object"
            },
            "meta": {
              "properties": {
                "computed_at": {
                  "type": "string"
                },
                "deterministic": {
                  "type": "boolean"
                },
                "disclaimer": {
                  "type": "string"
                },
                "price_usd": {
                  "type": "string"
                },
                "request_id": {
                  "type": "string"
                },
                "sources": {
                  "type": "array"
                }
              },
              "required": [
                "request_id",
                "computed_at",
                "price_usd",
                "deterministic",
                "disclaimer"
              ],
              "type": "object"
            },
            "ok": {
              "const": true,
              "type": "boolean"
            },
            "route": {
              "type": "string"
            },
            "version": {
              "type": "string"
            }
          },
          "required": [
            "ok",
            "route",
            "version",
            "data",
            "meta"
          ],
          "type": "object"
        },
        "type": {
          "type": "string"
        }
      },
      "required": [
        "type"
      ],
      "type": "object"
    }
  },
  "required": [
    "input"
  ],
  "type": "object"
}

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