API - Migration (API1-5 to API6) | API

API versions 1 through 5 have been shut down. Every integration must now use API version 6 (API6). If you have an older integration that stopped working, this article shows what to change.

API version	Shut down on	What a call returns now
API1, API2, API3, API5	April 1, 2026	HTTP `410 Gone`
API4	May 1, 2026	HTTP `410 Gone`
API6	Current version	Normal responses

Key Changes

Base URL: change /api1/, /api2/, /api3/, /api4/ or /api5/ to /api6/.
Response format: responses are standardized JSON.
The old IO mobile app stopped working because development of that application has ended. See API - Original InflatableOffice App End-of-Life.

How to Tell You Are Still on an Old Version

A call to a shut down version returns HTTP status 410 with a body like this:

{
  "error": "API Deprecated",
  "message": "This API version has been deprecated as of April 1, 2026. Please upgrade to API6."
}

If you see this, find the URL your integration calls and update the version number in it.

API Request Example

Old Method (No Longer Works)

GET /api2/rentals?apiKey=YOUR_API_KEY

New Method (Required)

GET /api6/rentals?apiKey=YOUR_API_KEY

Success response:

{
  "offset": 0,
  "limit": 25,
  ...
}

Code Examples

PHP

Old:

$url = "https://rental.software/api3/rentals?apiKey=" . urlencode($apiKey);
$response = file_get_contents($url);

New:

$url = "https://rental.software/api6/rentals?apiKey=" . urlencode($apiKey);
$response = file_get_contents($url);

cURL

Old:

curl "https://rental.software/api4/rentals?apiKey=YOUR_API_KEY"

New:

curl "https://rental.software/api6/rentals?apiKey=YOUR_API_KEY"

Error Codes

API6 errors come back as JSON with the HTTP status and a message, for example {"status": 401, "message": "API key not found"}.

Code	Description	Resolution
`401` Unauthorized	The API key is missing, mistyped, or blocked by an IP restriction	Verify the key and its settings under Settings > API Keys
`403` Forbidden	The key does not have permission for what it tried to do	Grant the permission on the API key
`404` Not Found	The resource or endpoint was not found	Verify the endpoint name is typed correctly and the ID exists
`405` Method Not Allowed	The wrong HTTP method was used (for example GET instead of POST)	Verify the allowed methods for that endpoint
`410` Gone	The call went to API version 1 through 5	Change the URL to `/api6/`
`429` Too Many Requests	The integration is calling too fast	Slow down and retry after the wait time

See API - Errors and Rate Limits for the full list.

Testing

# Test with a valid request
curl "https://rental.software/api6/rentals?apiKey=YOUR_API_KEY"
# Expected: {"offset":0, "limit":25, "count":"127", ...}

Migration Checklist

Update the base URL to /api6/ everywhere your integration calls the API.
Test each of your API calls.
Check that your code handles the error codes above.

Important Dates

April 1, 2026: API1, API2, API3 and API5 were shut down.
May 1, 2026: API4 was shut down, and the old IO mobile application stopped working.

API - Migration (API1-5 to API6)