🔐 AES-256 Military Grade
🔑 100,000 Key Iterations
🛡️ VirtualLock RAM Protection
⚡ Multi-threaded Processing
💚 100% Free Forever
🔒 HMAC-SHA256 Verification
🏗️ No External DLLs
📁 Timestamp Preserved
🔐 AES-256 Military Grade
🔑 100,000 Key Iterations
🛡️ VirtualLock RAM Protection
⚡ Multi-threaded Processing
💚 100% Free Forever
🔒 HMAC-SHA256 Verification
🏗️ No External DLLs
📁 Timestamp Preserved
FREE · Windows · No BS · Just Encryption

GREENBOX

Your Files. Your Keys. Your Rules.

Lock your files with the same encryption used by governments & militaries. Your documents become indecipherable noise — unless you hold the key. Free forever. No catch.

Download Free See It In Action
No account needed
No internet required
No telemetry
Zero external DLLs
Features

Everything. Nothing Wasted.

Every feature exists for a reason. No bloat. No fluff.

🔒
AES-256 CTR Mode
The gold standard used by the NSA for TOP SECRET documents. Your files get the same protection as state secrets.
Key: 256-bit · Mode: CTR · Rounds: 14
🧠
VirtualLock RAM Protection
Your key is locked in physical RAM. The OS can't page it to disk. Gone the moment encryption finishes.
⚡
Multi-threaded Speed
All CPU cores utilized. 1MB chunks fly through encryption in parallel — large files done in seconds.
🏛️
Windows Native Crypto API — Zero Dependencies
Only Windows BCrypt (built-in). No OpenSSL. No DLL hell. No supply chain attacks. Audited by Microsoft for decades.
API: Windows CNG · Provider: BCrypt.dll · External DLLs: 0
🛡️
Dual HMAC Verification
Two HMAC-SHA256 passes before any write. Tampered file? Wrong key? Corrupted data? Nothing gets written.
🕒
Timestamp Preservation
Real creation & modification times stored inside the encrypted file. Decrypt and your file is restored exactly as it was.
💚
100% Free — Forever
No subscription. No trial. No "pro" tier. Personal & commercial use. Because privacy is a right, not a luxury.
Live Demo

Watch Your File Disappear Into Noise

Without your password, it's pure random chaos — mathematically impossible to reverse.

Awaiting command — click Animate to see encryption in action
2256
Possible Keys
0
PBKDF2 Iterations
0
HMAC Checks
$0
Forever
Process

From File to Fortress in Seconds

Simple to use. Insanely complex underneath.

📁
Pick File
Any file type, any size
🔑
Password
Never leaves your machine
🔥
100K Stretches
PBKDF2 key derivation
⚡
AES-256
Multi-threaded CTR mode
✅
HMAC Signed
Dual verification output
Questions

We've Heard Everything

Is it really free? What's the catch?
▼
There is no catch. No subscription, no trial, no ads, no telemetry, no data collection. We built GreenBox because everyone deserves privacy — not just people who can afford enterprise software. Use it personally, commercially, forever. The only thing we ask is nothing.
What happens if I forget my password?
▼
Your file is gone. And we mean that in the best possible way. No backdoor, no recovery mechanism. Your password is the key. No key = no access. This is by design — a backdoor for you is a backdoor for attackers too.
Can hackers break the encryption?
▼
Mathematically, no. AES-256 has never been broken. The best known attack is brute force, which would take longer than the age of the universe with all computing power on Earth. PBKDF2 with 100,000 iterations makes password guessing infeasible. Your encrypted file is safe anywhere.
Does GreenBox phone home?
▼
Absolutely not. Zero network connections. Ever. No analytics, no update checker, no crash reporting. Your files, your password, your machine. Works perfectly on air-gapped systems with no network.

Your Files Deserve
Real Protection

Download GreenBox and encrypt your first file in under 60 seconds. Military-grade security doesn't have to cost you anything.

Download GreenBox — Free
🪟 Windows 10/11 ⚡ No Install Required 📦 Portable EXE
256
Bit Keys
100K
Iterations
$0
Forever