const formData = new FormData();
formData.append("file", fileInput.files[0]);
formData.append("output_format", "pdf");
formData.append("engine", "default");
formData.append("language", "fa");

fetch("https://api.filekit.ir/v1/convert", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_API_KEY",
    "Accept": "application/json"
  },
  body: formData
})
  .then(response => response.json())
  .then(data => console.log(data))
  .catch(error => console.error(error));

const axios = require("axios");
const FormData = require("form-data");
const fs = require("fs");

const form = new FormData();
form.append("file", fs.createReadStream("input.txt"));
form.append("output_format", "pdf");
form.append("engine", "default");
form.append("language", "fa");

axios.post("https://api.filekit.ir/v1/convert", form, {
  headers: {
    ...form.getHeaders(),
    Authorization: "Bearer YOUR_API_KEY",
    Accept: "application/json"
  }
}).then(res => {
  console.log(res.data);
});

<?php

$url = "https://api.filekit.ir/v1/convert";

$data = [
    "file" => new CURLFile("input.txt"),
    "output_format" => "pdf",
    "engine" => "default",
    "language" => "fa"
];

$headers = [
    "Authorization: Bearer YOUR_API_KEY",
    "Accept: application/json"
];

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

$response = curl_exec($ch);
echo $response;

curl_close($ch);

curl -X POST "https://api.filekit.ir/v1/convert" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Accept: application/json" \
  -F "file=@input.txt" \
  -F "output_format=pdf" \
  -F "engine=default" \
  -F "language=fa"