Generate a key to send texts
If you already have one, add funds to an existing key.
×
A simple API for one-time password mobile verification via text message
We take the SMS headache out of mobile verification and one-time passwords (OTPs).
Use this API to verify user identity (mobile verification) or possession of a device (OTP/two-factor authentication):
Since its creation, Textbelt has sent over 3 million texts and OTPs from the command line and other software clients!
OTP generation does not require client libraries or an account. The verification code is automatically sent to the user's phone:
$ curl -X POST https://textbelt.com/otp/generate \
--data-urlencode phone='5557727420' \
--data-urlencode userid='myuser@site.com' \
-d key=example_otp_key
import requests
requests.post('https://textbelt.com/otp/generate', {
'phone': '5557727420',
'userid': 'myuser@site.com',
'key': 'example_otp_key',
})require 'net/http'
require 'uri'
uri = URI.parse("https://textbelt.com/otp/generate")
Net::HTTP.post_form(uri, {
:phone => '5557727420',
:userid => 'myuser@site.com',
:key => 'example_otp_key',
})var request = require('request');
request('https://textbelt.com/otp/generate', {
body: {
phone: '5557727420',
userid: 'myuser@site.com',
key: 'example_otp_key',
},
})using System;
using System.Collections.Specialized;
using System.Net;
using (WebClient client = new WebClient())
{
byte[] response = client.UploadValues("http://textbelt.com/text", new NameValueCollection() {
{ "phone", "5557727420" },
{ "userid", "myuser@site.com" },
{ "key", "example_otp_key" },
});
string result = System.Text.Encoding.UTF8.GetString(response);
}$ch = curl_init('https://textbelt.com/otp/generate');
$data = array(
'phone' => '5557727420',
'userid' => 'myuser@site.com',
'key' => 'example_otp_key',
);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($data));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);
curl_close($ch);
final NameValuePair[] data = {
new BasicNameValuePair("phone", "5557727420"),
new BasicNameValuePair("userid", "myuser@site.com"),
new BasicNameValuePair("key", "example_otp_key")
};
HttpClient httpClient = HttpClients.createMinimal();
HttpPost httpPost = new HttpPost("https://textbelt.com/otp/generate");
httpPost.setEntity(new UrlEncodedFormEntity(Arrays.asList(data)));
HttpResponse httpResponse = httpClient.execute(httpPost);
String responseString = EntityUtils.toString(httpResponse.getEntity());
JSONObject response = new JSONObject(responseString);
Try it now! userid can be anything that uniquely identifies users. Use key "example_otp_key" to send an example one-time password. You'll need your own key to send an actual OTP.
To text internationally, use the E.164 format when setting phone (+ country code with numbers, no spaces). For example, a Brazilian phone number is +5511912345678 and a UK phone number is +447712345678.
After the user receives the text message, they'll input the verification code in your app. Textbelt will tell you if that code is valid.
Supply the otp to verify, a userid, and your Textbelt key via GET request:
Send and verify OTPs by creating an API key:
{"success": true, "textId": "1234", "quotaRemaining": 70, "otp": "672383"}
Check success to determine whether the OTP was sent to the user.
This means the user was sent a text containing an OTP. By default the message format is: "Your verification code is 672 383".
There are a few parameters you can add to your request:
message will replace the default OTP message. Use the $OTP variable to include the OTP.lifetime will determine how many seconds the OTP is valid for. If you set lifetime to 240, the OTP will be valid for 240 seconds or 4 minutes.$ curl -X POST https://textbelt.com/otp/generate \
--data-urlencode phone='5557727420' \
--data-urlencode name='myuser@site.com' \
--data-urlencode message='Nuclear launch code: $OTP! Use it to login.' \
-d lifetime=120 \
-d key=example_otp_key
Example out-of-quota or invalid key response from /otp/generate:
{"success": false, "quotaRemaining": 0, "otp": ""}
Here's an example valid OTP response from /otp/verify.
Check isValidOtp to decide whether the OTP has been approved:
{"success": true, "isValidOtp": true}
Example response for an invalid OTP. Note that "success" indicates a successful response, not a successful OTP:
{"success": true, "isValidOtp": false}
OTP keys are the same as normal Textbelt keys. This means you can mix and match your quota to send OTPs and normal text messages.
You're ready to go! Fill out the form below to generate a key.
If you already have one, add funds to an existing key.
Any questions? Email support@textbelt.com, text +1 (650) 332-4607, or read the FAQ.
If you already have one, add funds to an existing key.
You should record this key somewhere safe.