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A 403 from Html2Pdf.app has a documented cause: the account has reached a limit on its current plan. A 429 is different—the provider’s published status table does not explain what triggers it or how to recover. Check which status you actually received before changing your request or retrying.
First, verify the request and response
The documented conversion endpoint is POST https://api.html2pdf.app/v1/generate. Send a JSON body and authenticate with the X-API-Key header. Keep the API key on a trusted server, backend script, or job; do not expose it in browser JavaScript, client-side templates, or a public repository. See Html2Pdf.app’s API documentation for the request format and status guidance.
- Confirm the method is
POST, the URL ishttps://api.html2pdf.app/v1/generate, the body is valid JSON, and the request includesX-API-Key. - Read and record the HTTP status before treating the response as a PDF. Html2Pdf.app says non-2xx responses are errors; do not save them as PDFs or serve them with an
application/pdfcontent type. - Use the status-specific guidance below. The same response body or retry behavior should not be assumed to mean the same thing across different status codes.
What a 403 means
Html2Pdf.app documents 403 as an account that has reached a limit included in its current plan. Review the plan limits and check the notification email sent to the account. After resolving the account-limit issue, retry the request.
Do not automatically retry an unchanged 403. The provider explicitly advises against automatically retrying 400, 401, or 403 before correcting the request, credentials, or account limit.
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What to do about a 429
The provider’s published status table does not define 429. It does not establish the trigger, a rate-limit window, relevant response headers, or a retry schedule. The documented explanation for 403 does not establish the cause of a 429, so do not assume that a 429 means the plan limit has been reached.
Keep the status and any response details available, then ask Html2Pdf.app support for the account-specific cause and recommended recovery. The reviewed provider material does not establish whether or when to retry a 429; do not present a retry interval as provider guidance.
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Check nearby status codes separately
| Status | Documented meaning | Next step |
|---|---|---|
400 |
Inaccessible source URL or invalid request parameter | Check that the input URL is accessible and the parameters are valid. |
401 |
API key is missing or invalid | Check the key and confirm it is sent in the X-API-Key header. |
403 |
The account has reached a limit included in its current plan | Review plan limits and the account notification email; resolve the limit before retrying. |
429 |
Not defined in the provider’s published status table | Preserve the response details and ask support for the trigger and recovery guidance. |
500 |
Unhandled server error | The provider suggests retrying after a short delay, increasing delays between repeated attempts, and contacting support if the error persists. |
These meanings and actions are from Html2Pdf.app’s documentation; the 500 retry guidance is specific to 500 and should not be transferred to 429.
Reproduce and inspect a request with cURL
The provider’s cURL guide shows how to send a request, check for non-2xx results, and keep the key in an environment variable. Adapt the JSON body to the parameters your conversion needs:
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export HTML2PDF_API_KEY='your-api-key'
curl --fail-with-body -X POST 'https://api.html2pdf.app/v1/generate'
-H "X-API-Key: $HTML2PDF_API_KEY"
-H 'Content-Type: application/json'
-d '{"url":"https://example.com"}'
-o output.pdf--fail-with-body makes cURL return an error for an HTTP failure while retaining the response body, which can help with diagnosis. Check the HTTP status in the command output or with your HTTP client before using the saved file; an error response is not a PDF. The provider’s guide also notes that a blank or unstyled output can result when the source URL or its CSS, fonts, or images are not publicly reachable. Those checks diagnose input or rendering problems, not a documented explanation for 429.
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