API URL
POST /calculate
Headers
Code
Content-Type: application/jsonBody Parameters
Param
Type
Description
start_date
required
string
Base date for calculation
end_date
required
string
End of date range
days_offset
required
integer
Working-day delta (if no end_date)
direction
optional
string
Direction: forward (default) or backward
date_format
optional
string
Input format (e.g. MM/DD/YYYY)
custom_holidays
optional
array
Extra holidays to exclude
region
optional
string
ISO 3166-1 alpha-2 (default: US)
include_start
optional
boolean
Include start date in count
batch
optional
array
For bulk requests
Content-Type
required
string
Must be application/json for POST requests
Example Request
Code
{
"start_date": "2025-07-01",
"end_date": "2025-07-10",
"region": "US"
}Successful Response
Status
HTML
200 OKBody
Code
{
"working_days": 7,
"start_date": "2025-07-01",
"end_date": "2025-07-10",
"region": "US",
"holidays_used": [
"2025-07-04"
]
}Field
Type
Description
success
boolean
—
data
object
—
working_days
integer
Total calculated business days excluding weekends and public holidays for accurate project timeline planning
start_date
string
Normalized starting date in ISO format ensuring consistent business day calculation baseline
end_date
string
Final business date or calculated target date for project milestone and deadline management
result_date
string
—
region
string
Country or regional holiday calendar applied ensuring compliance with local business practices
holidays_used
array
—
calculation_type
string
—
total_days
integer
—
weekends_excluded
integer
—
holidays_excluded
integer
List of public holidays removed from business day count for transparent calculation auditing
holidays_list
array
—
meta
object
—
meta.batchSize
integer
—
meta.successCount
integer
—
meta.errorCount
integer
—
meta.processingTimeMs
integer
—
meta.timestamp
string
—
meta.epochTime
integer
—
correlationId
string
—
error
string
—
Error Response
Example
Code
400 INVALID_DATE – Date could not be parsed
400 INVALID_REGION – Region code not valid
400 MISSING_INPUT – Missing end_date or offset
429 RATE_LIMIT – If limits exceeded (future use)Last Updated: May 4, 2026