> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pdfshift.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Response headers

When you do a successful call to the `/convert/{pdf|jpeg|png|webp}` endpoint, the response will contain a few custom headers that can help you better trace the whole requests througout our system.

Here's the list of headers returned by PDFShift:

<ParamField header="X-Response-Status-Code" type="Integer">
  Provides the status code PDFShift got when loading your source when it is an HTTP request.
</ParamField>

<ParamField header="X-PDFShift-Processor" type="String">
  Returns the name of the PDFShift's server that ran the conversion.
</ParamField>

<ParamField header="X-Credits-Cost" type="Integer">
  Indicates the number of credits that this generation requires.
</ParamField>

<ParamField header="X-Credits-Used" type="Integer">
  Contrary to `X-Credits-Cost`, this header indicates the number of credits that were decreased from your account.
  It is identical to `X-Credits-Cost` excepted if you passed the `sandbox` parameter, in which case the value will be at 0.
</ParamField>

<ParamField header="X-Response-Duration" type="Integer">
  The number of miliseconds it took to load the HTML source provided in the request.
</ParamField>

<ParamField header="X-PDFShift-Duration" type="Integer">
  The number of miliseconds it took to load the source and then generate the PDF document.
  This value should be closer to the Time To First Byte duration you can have on your end.
</ParamField>