API: IV analytics
Single-expiry smile
One expiry’s implied-vol smile from the fitted surface, by strike and log-moneyness, with its ATM, risk reversals, butterflies and arbitrage checks.
GET
/
options
/
iv
/
smile
Single-expiry IV smile
curl --request GET \
--url https://api.example.com/options/iv/smile \
--header 'X-API-Key: <api-key>'import requests
url = "https://api.example.com/options/iv/smile"
headers = {"X-API-Key": "<api-key>"}
response = requests.get(url, headers=headers)
print(response.text)const options = {method: 'GET', headers: {'X-API-Key': '<api-key>'}};
fetch('https://api.example.com/options/iv/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.example.com/options/iv/smile",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "GET",
CURLOPT_HTTPHEADER => [
"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"
"net/http"
"io"
)
func main() {
url := "https://api.example.com/options/iv/smile"
req, _ := http.NewRequest("GET", url, nil)
req.Header.Add("X-API-Key", "<api-key>")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.get("https://api.example.com/options/iv/smile")
.header("X-API-Key", "<api-key>")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.example.com/options/iv/smile")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Get.new(url)
request["X-API-Key"] = '<api-key>'
response = http.request(request)
puts response.read_body{
"success": false,
"error": {
"code": "UNAUTHORIZED",
"message": "Invalid API key"
},
"meta": {
"version": "2.0",
"timestamp": "2026-04-29T12:00:00Z"
}
}{
"success": false,
"error": {
"code": "NOT_FOUND",
"message": "No data for BTCUSDT"
},
"meta": {
"version": "2.0",
"timestamp": "2026-04-29T12:00:00Z"
}
}{
"success": false,
"error": {
"code": "VALIDATION_ERROR",
"message": "Invalid request parameters",
"details": {
"errors": []
}
},
"meta": {
"version": "2.0",
"timestamp": "2026-04-29T12:00:00Z"
}
}{
"success": false,
"error": {
"code": "RATE_LIMIT_EXCEEDED",
"message": "Rate limit exceeded. Try again later."
},
"meta": {
"version": "2.0",
"timestamp": "2026-04-29T12:00:00Z"
}
}One expiry’s smile, rebuilt from its SVI fit between its lowest and highest
quoted strikes and never past them (
method: svi), or its row of the surface grid where the smile
did not fit (method: interp, mostly same-day expiries). Each point gives
the strike, the log-moneyness against the expiry’s own forward and the vol
in percent.
The response adds the expiry’s ATM vol, 25- and 10-delta risk reversals and
butterflies, the fit error smile_rmse, and its static-arbitrage checks:
butterfly_free (non-negative density across the quoted strikes, with
min_density_g) and calendar_free (its total variance is at or above the
previous fitted expiry’s). Both are null on an interp row.
expiry takes a token (30OCT26) or an ISO date (2026-10-30); omitted,
the nearest fitted expiry is returned. available_expiries lists every
expiry you can ask for, including fitted ones past the grid’s 180 days.
call_ivs and put_ivs are deprecated and always null.
See also
Vol surface methodology
Constant-maturity vol
IV suite
Authorizations
Your BackQuant API key (same key as v1)
Headers
Query Parameters
Trading symbol: BTCUSDT, ETHUSDT, SOLUSDT, or HYPEUSDT.
Available options:
BTCUSDT, ETHUSDT, SOLUSDT, HYPEUSDT Expiry token (30OCT26) or ISO date. Omit for the nearest fitted expiry.
Response
Successful Response
⌘I
Single-expiry IV smile
curl --request GET \
--url https://api.example.com/options/iv/smile \
--header 'X-API-Key: <api-key>'import requests
url = "https://api.example.com/options/iv/smile"
headers = {"X-API-Key": "<api-key>"}
response = requests.get(url, headers=headers)
print(response.text)const options = {method: 'GET', headers: {'X-API-Key': '<api-key>'}};
fetch('https://api.example.com/options/iv/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.example.com/options/iv/smile",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "GET",
CURLOPT_HTTPHEADER => [
"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"
"net/http"
"io"
)
func main() {
url := "https://api.example.com/options/iv/smile"
req, _ := http.NewRequest("GET", url, nil)
req.Header.Add("X-API-Key", "<api-key>")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.get("https://api.example.com/options/iv/smile")
.header("X-API-Key", "<api-key>")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.example.com/options/iv/smile")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Get.new(url)
request["X-API-Key"] = '<api-key>'
response = http.request(request)
puts response.read_body{
"success": false,
"error": {
"code": "UNAUTHORIZED",
"message": "Invalid API key"
},
"meta": {
"version": "2.0",
"timestamp": "2026-04-29T12:00:00Z"
}
}{
"success": false,
"error": {
"code": "NOT_FOUND",
"message": "No data for BTCUSDT"
},
"meta": {
"version": "2.0",
"timestamp": "2026-04-29T12:00:00Z"
}
}{
"success": false,
"error": {
"code": "VALIDATION_ERROR",
"message": "Invalid request parameters",
"details": {
"errors": []
}
},
"meta": {
"version": "2.0",
"timestamp": "2026-04-29T12:00:00Z"
}
}{
"success": false,
"error": {
"code": "RATE_LIMIT_EXCEEDED",
"message": "Rate limit exceeded. Try again later."
},
"meta": {
"version": "2.0",
"timestamp": "2026-04-29T12:00:00Z"
}
}