curl --request POST \
  --url https://api.fincept.in/quantlib/volatility/sabr/smile \
  --header 'Content-Type: application/json' \
  --header 'X-API-Key: <api-key>' \
  --data '
{
  "forward": 100,
  "expiry": 1,
  "alpha": 0.25,
  "beta": 0.5,
  "rho": -0.2,
  "nu": 0.3,
  "strikes": [
    90,
    95,
    100,
    105,
    110
  ]
}
'

import requests

url = "https://api.fincept.in/quantlib/volatility/sabr/smile"

payload = {
    "forward": 100,
    "expiry": 1,
    "alpha": 0.25,
    "beta": 0.5,
    "rho": -0.2,
    "nu": 0.3,
    "strikes": [90, 95, 100, 105, 110]
}
headers = {
    "X-API-Key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'X-API-Key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    forward: 100,
    expiry: 1,
    alpha: 0.25,
    beta: 0.5,
    rho: -0.2,
    nu: 0.3,
    strikes: [90, 95, 100, 105, 110]
  })
};

fetch('https://api.fincept.in/quantlib/volatility/sabr/smile', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.fincept.in/quantlib/volatility/sabr/smile",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'forward' => 100,
    'expiry' => 1,
    'alpha' => 0.25,
    'beta' => 0.5,
    'rho' => -0.2,
    'nu' => 0.3,
    'strikes' => [
        90,
        95,
        100,
        105,
        110
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-API-Key: <api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.fincept.in/quantlib/volatility/sabr/smile"

	payload := strings.NewReader("{\n  \"forward\": 100,\n  \"expiry\": 1,\n  \"alpha\": 0.25,\n  \"beta\": 0.5,\n  \"rho\": -0.2,\n  \"nu\": 0.3,\n  \"strikes\": [\n    90,\n    95,\n    100,\n    105,\n    110\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("X-API-Key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.fincept.in/quantlib/volatility/sabr/smile")
  .header("X-API-Key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"forward\": 100,\n  \"expiry\": 1,\n  \"alpha\": 0.25,\n  \"beta\": 0.5,\n  \"rho\": -0.2,\n  \"nu\": 0.3,\n  \"strikes\": [\n    90,\n    95,\n    100,\n    105,\n    110\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.fincept.in/quantlib/volatility/sabr/smile")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["X-API-Key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"forward\": 100,\n  \"expiry\": 1,\n  \"alpha\": 0.25,\n  \"beta\": 0.5,\n  \"rho\": -0.2,\n  \"nu\": 0.3,\n  \"strikes\": [\n    90,\n    95,\n    100,\n    105,\n    110\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "success": true,
  "data": {
    "forward": 100,
    "expiry": 1,
    "atm_vol": 0.25,
    "skew": -0.0015,
    "curvature": 0.00008,
    "smile": [
      {
        "strike": 90,
        "implied_vol": 0.268
      },
      {
        "strike": 95,
        "implied_vol": 0.257
      },
      {
        "strike": 100,
        "implied_vol": 0.25
      },
      {
        "strike": 105,
        "implied_vol": 0.248
      },
      {
        "strike": 110,
        "implied_vol": 0.251
      }
    ]
  }
}

{
  "detail": "Invalid API key"
}

{
  "detail": "Endpoint requires Standard tier or higher"
}

{
  "detail": [
    {
      "loc": [
        "body",
        "volatility"
      ],
      "msg": "field required",
      "type": "value_error.missing"
    }
  ]
}