When users submit a form on your website, where does that data go? For most form builders, the answer is: straight to their servers, in plaintext.
This means the form provider can read every email, phone number, and sensitive detail your users submit. They might not want to, but they can. And so can anyone who breaches their systems.
The Problem with Server-Side Encryption
Many form services advertise “encryption” as a feature. But here’s the catch: they encrypt data after it reaches their servers. This is called server-side encryption, and it has a fundamental flaw.
The provider holds the keys.
If the form provider has the encryption keys, they can decrypt your data at any time. This means:
- Data breaches expose everything: Hackers who access their systems can decrypt all stored data
- Insider threats are real: Employees with database access can view sensitive submissions
- Legal compulsion: Governments can compel companies to decrypt and hand over data
- Third-party access: Analytics tools and integrations may process plaintext data
What is Client-Side Encryption?
Client-side encryption flips the model. Instead of sending plaintext to a server that then encrypts it, the encryption happens in the user’s browser before any data is transmitted.
Here’s how it works:
- User fills out a form
- JavaScript in the browser encrypts the data using your public key
- Only encrypted ciphertext is sent to the server
- The server stores the ciphertext (it cannot decrypt it)
- You decrypt submissions using your private key
The key difference: The server never sees plaintext. It only stores encrypted blobs that are mathematically impossible to decrypt without your private key.
Real-World Security Benefits
Protection Against Data Breaches
If a form provider’s database is breached, attackers get… encrypted gibberish. Without your private key (which never touches their servers), the data is useless.
Compare this to traditional form builders where a breach exposes:
- Full names and addresses
- Email addresses and phone numbers
- Payment information
- Health data, legal information, and more
Insider Threat Mitigation
Even with the best intentions, companies have rogue employees. Client-side encryption means a database administrator at your form provider cannot read your submissions—they simply don’t have the keys.
Compliance Made Simple
Regulations like GDPR, HIPAA, and CCPA require data minimization and protection. Client-side encryption provides:
- Data minimization: The processor (form provider) only handles encrypted data
- Privacy by design: Encryption is built into the data flow, not bolted on
- Reduced liability: You maintain control of the decryption keys
The Technical Implementation
VeilForms uses a hybrid encryption approach combining RSA-2048 and AES-256:
1. Generate random AES-256 key
2. Encrypt form data with AES-256-GCM
3. Encrypt AES key with your RSA-2048 public key
4. Send encrypted data + encrypted key to server
This gives you:
- Speed: AES-256 is fast for bulk data encryption
- Security: RSA-2048 protects the AES key
- Forward secrecy: Each submission uses a unique AES key
When Should You Use Client-Side Encryption?
Client-side encryption is essential when collecting:
- Healthcare information: Patient forms, medical history, symptom trackers
- Financial data: Loan applications, income verification, tax information
- Legal information: Case intake forms, witness statements
- HR data: Employee complaints, salary negotiations, exit interviews
- Personal identifiers: SSNs, passport numbers, driver’s licenses
Even for “non-sensitive” forms, client-side encryption provides peace of mind. Why risk it when you don’t have to?
Getting Started with VeilForms
Adding client-side encryption to your forms takes minutes:
<form data-veilform="YOUR_FORM_ID">
<input name="email" type="email" required>
<textarea name="message"></textarea>
<button type="submit">Send</button>
</form>
<script src="https://cdn.veilforms.com/v1/veilforms.esm.js"></script>
That’s it. Every submission is now encrypted in the browser before transmission.
Client-side encryption isn’t just a feature—it’s a fundamental shift in how we think about form data. Instead of trusting third parties with sensitive information, you maintain control.
Your users’ privacy depends on it.