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Tools.Town
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Time Duration Calculator API

Enter a start time and an end time to see elapsed hours, minutes, and seconds — including overnight (11pm to 2am) and stacked timesheet segments.

Category: Date & Time Endpoint: /v1/date/duration Method: POST Auth: API Key

Fast & Accurate

Get precise results instantly.

Easy Integration

Simple REST API with JSON response.

Developer Friendly

Clear docs and SDK examples.

Free to Start

5,000 free requests/month.

Endpoint

All requests should be made to the following endpoint:

POSThttps://api.tools.town/v1/date/duration

Authentication

This endpoint requires an API Key. Include your API key in the request header.

Authorization: Bearer YOUR_API_KEY
You can get your API key from your dashboard.

Request Parameters

Send a POST request with JSON body.

ParameterTypeRequiredDescriptionExample
modestringsum or diff.sum
durationsarrayDurations to add (HH:MM:SS strings).["01:30:00","02:15:00"]

Example Request

curl -X POST "https://api.tools.town/v1/date/duration" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "mode": "sum",
    "durations": ["01:30:00","02:15:00"]
  }'

Example Response 200 OK

application/json
{
  "success": true,
  "data": {
    "totalSeconds": "0",
    "formatted": "string",
    "hoursDecimal": "0"
  }
}

Error Codes

CodeMeaning
400Bad Request — missing or invalid parameter
401Unauthorized — API key missing or invalid
429Rate limit exceeded — free tier: 5,000 requests/month
500Internal Server Error — try again or contact support