Stop form spam without CAPTCHA

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Integrate in minutes with a single API call

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Check form submissions with a single request

FormSentry quietly analyses each submission and tells you whether it's legitimate or spam - no CAPTCHA, no user interaction.

# Verify a form submission with FormSentry
curl -X POST https://api.formsentry.ai/v1/verify \
  -H "Content-Type: application/json" \
  -d '{
    "apiKey": "YOUR-API-KEY",
    "formId": "YOUR-FORM-ID",
    "payload": {
      "name": "John Doe",
      "email": "john@example.com",
      "message": "This is a test form only"
    }
  }'

# Response: { status, confidence, reasoning, submissionId, processingTime, formId }
# 
# If status is "spam", silently reject the submission
# Otherwise, process it as legitimate

const https = require('https');

// Verify a form submission with FormSentry
const data = JSON.stringify({
  apiKey: 'YOUR-API-KEY',
  formId: 'YOUR-FORM-ID',
  payload: {
    name: 'John Doe',
    email: 'john@example.com',
    message: 'This is a test form only'
  }
});

const options = {
  hostname: 'api.formsentry.ai',
  port: 443,
  path: '/v1/verify',
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Content-Length': data.length
  }
};

const req = https.request(options, (res) => {
  let body = '';
  
  res.on('data', (chunk) => {
    body += chunk;
  });
  
  res.on('end', () => {
    const result = JSON.parse(body);
    // result: { status, confidence, reasoning, submissionId, processingTime, formId }
    
    if (result.status === 'spam') {
      console.log('Spam detected - silently reject');
    } else {
      console.log(`Legitimate submission (confidence: ${result.confidence})`);
    }
  });
});

req.on('error', (error) => {
  console.error(error);
});

req.write(data);
req.end();

// Verify a form submission with FormSentry
const response = await fetch('https://api.formsentry.ai/v1/verify', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    apiKey: 'YOUR-API-KEY',
    formId: 'YOUR-FORM-ID',
    payload: {
      name: 'John Doe',
      email: 'john@example.com',
      message: 'This is a test form only'
    }
  })
});

const result = await response.json();
// result: { status, confidence, reasoning, submissionId, processingTime, formId }

if (result.status === 'spam') {
  console.log('Spam detected - silently reject');
} else {
  console.log(`Legitimate submission (confidence: ${result.confidence})`);
}

import requests

# Verify a form submission with FormSentry
response = requests.post(
    'https://api.formsentry.ai/v1/verify',
    headers={
        'Content-Type': 'application/json'
    },
    json={
        'apiKey': 'YOUR-API-KEY',
        'formId': 'YOUR-FORM-ID',
        'payload': {
            'name': 'John Doe',
            'email': 'john@example.com',
            'message': 'This is a test form only'
        }
    }
)

result = response.json()
# result: { status, confidence, reasoning, submissionId, processingTime, formId }

if result['status'] == 'spam':
    print('Spam detected - silently reject')
else:
    print(f"Legitimate submission (confidence: {result['confidence']})")

<?php
// Verify a form submission with FormSentry
$ch = curl_init('https://api.formsentry.ai/v1/verify');

curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST => true,
    CURLOPT_HTTPHEADER => [
        'Content-Type: application/json'
    ],
    CURLOPT_POSTFIELDS => json_encode([
        'apiKey' => 'YOUR-API-KEY',
        'formId' => 'YOUR-FORM-ID',
        'payload' => [
            'name' => 'John Doe',
            'email' => 'john@example.com',
            'message' => 'This is a test form only'
        ]
    ])
]);

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

$result = json_decode($response, true);
// result: { status, confidence, reasoning, submissionId, processingTime, formId }

if ($result['status'] === 'spam') {
    error_log('Spam detected - silently reject');
} else {
    error_log("Legitimate submission (confidence: {$result['confidence']})");
}
?>

require 'net/http'
require 'json'

# Verify a form submission with FormSentry
uri = URI('https://api.formsentry.ai/v1/verify')
http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = true

request = Net::HTTP::Post.new(uri.path, {
  'Content-Type' => 'application/json'
})

request.body = {
  apiKey: 'YOUR-API-KEY',
  formId: 'YOUR-FORM-ID',
  payload: {
    name: 'John Doe',
    email: 'john@example.com',
    message: 'This is a test form only'
  }
}.to_json

response = http.request(request)
result = JSON.parse(response.body)
# result: { status, confidence, reasoning, submissionId, processingTime, formId }

if result['status'] == 'spam'
  puts 'Spam detected - silently reject'
else
  puts "Legitimate submission (confidence: #{result['confidence']})"
end

See Docs

Invisible protection that works

Why teams replace CAPTCHA with FormSentry

Better user experience, better data, and better results - without trade-offs

Higher form completion rates

Remove puzzles and friction so real users can submit forms without interruption.

Stops human spam

Detects low-quality, copy-pasted, and manually submitted spam - even when it looks “human”.

Integrates in minutes

Add FormSentry with a single API call - no UI changes, no refactors.

Stops sophisticated bots

Identifies automated submissions generated by modern AI tools and scripted attacks.

Works invisibly in the background

One request per submission. No UI changes. No impact on user experience.

Privacy-first by design

No cookies, no trackers, no behavioural profiling - just server-side verification.

FAQs

Frequently Asked Questions

Everything you need to know about how FormSentry protects your forms without CAPTCHA.

Is FormSentry Free?

Yes - FormSentry offers a free tier that allows you to protect your forms without any cost. You can sign up for a free account and start using FormSentry right away. We also offer paid plans with additional usage limits.

Does it work with any form?

FormSentry is designed to work with any form on your website or app. You can integrate it with contact forms, registration forms, comment forms, or any other type of form. Simply send the form data to our API for verification.

Is there a WordPress plugin for FormSentry?

Yes - we have a WordPress plugin that makes it easy to integrate FormSentry with your WordPress site and popular forms. You can install the plugin from the WordPress plugin repository and follow the instructions to connect it to your FormSentry account.

What is FormSentry's spam detection accuracy?

Spam detection accuracy can be as high as 99.99%+. FormSentry provides the ability to train the model based on historical legitimate and spam submissions in addition to your own spam training data inputs which will result in very high spam detection accuracy for your specific forms.

How do I improve FormSentry accuracy for my forms?

To improve accuracy, you can train the model with your historical form submission data (both legitimate and spam) and add your own examples. Accurate form names and descriptions also greatly improve accuracy. You don't need a lot of example data. Just a few targeted examples which you can easily adjust over time.

Is FormSentry better for privacy than reCAPTCHA?

Yes - FormSentry is designed to protect user privacy. FormSentry is a simple API call and does not require any end user cookies, browser session data or tracking scripts. Data retention for your form submissions is set by you for automatic and manual deletion. All submissions are not retained by us to train our models.

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No puzzles. No traffic lights. No checkboxes.
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