No install required — open it directly in your browser:
Download the html file from the latest web release to keep on your computer and run the program offline locally.
Works on any device with a modern browser. Everything runs locally — nothing is sent anywhere.
Encrypt & Decrypt Data Utility Tool is a password-based text encryption and decryption utility built for privacy and simplicity. It lets you lock any message behind a password so that only someone with the correct password can read it. All cryptographic operations happen locally on your device — nothing is transmitted, logged, or stored.
The tool uses AES-256-GCM encryption combined with PBKDF2-SHA256 key derivation (100,000 iterations), giving you strong, industry-standard security without needing a technical background to use it.
It was originally built as an internal utility tool and has since been rewritten as a standalone, open-source application available across multiple platforms.
| Platform | Status | Notes |
|---|---|---|
| Android | ✅ Released | Available on Google Play - Open in PlayStore |
| Web | ✅ Released | Open in browser — single HTML file, no server required |
| iOS | 🔧 Work in progress | SwiftUI — not yet released |
| Desktop | 📋 Planned | Native desktop application — coming in a future release |
Language support is being tracked across all platform versions. The web version and Android app currently include multilingual support.
The web and Android versions currently support English, German, Simplified Chinese, Traditional Chinese, Japanese, Korean, French, Spanish, Italian, Portuguese, Arabic, and Farsi. Arabic and Farsi include right-to-left layout support. More languages are planned — see the table below.
| Language | Web | Android | iOS | Desktop |
|---|---|---|---|---|
| English | ✅ | ✅ | 📋 Planned | 📋 Planned |
| German / Deutsch | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Simplified Chinese / 中文（简体） | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Traditional Chinese / 中文（繁體） | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Japanese / 日本語 | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Korean / 한국어 | ✅ | ✅ | 📋 Planned | 📋 Planned |
| French / Français | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Spanish / Español | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Italian / Italiano | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Portuguese / Português | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Arabic / العربية | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Farsi / فارسی | ✅ | ✅ | 📋 Planned | 📋 Planned |
| Russian / Русский | 📋 Planned | 📋 Planned | 📋 Planned | 📋 Planned |
| Ukrainian / Українська | 📋 Planned | 📋 Planned | 📋 Planned | 📋 Planned |
| Croatian / Serbian / Bosnian | 📋 Planned | 📋 Planned | 📋 Planned | 📋 Planned |
| Turkish / Türkçe | 📋 Planned | 📋 Planned | 📋 Planned | 📋 Planned |
| Indonesian / Bahasa Indonesia | 📋 Planned | 📋 Planned | 📋 Planned | 📋 Planned |
| Vietnamese / Tiếng Việt | 📋 Planned | 📋 Planned | 📋 Planned | 📋 Planned |
| Swahili / Kiswahili | 📋 Planned | 📋 Planned | 📋 Planned | 📋 Planned |
| Hausa / Harshen Hausa | 📋 Planned | 📋 Planned | 📋 Planned | 📋 Planned |
| Yoruba / Èdè Yorùbá | 📋 Planned | 📋 Planned | 📋 Planned | 📋 Planned |
Currently implemented on the web version:
index.htmlprivacy-policy.html
Currently implemented on the Android version:
app/src/main/assets/EncryptDecryptToolWeb.html
Your data is yours. Because this tool uses industry-standard algorithms, you can decrypt your messages using standard command-line tools without needing this software.
- Open the app and tap Encrypt.
- Enter the text you want to protect.
- Enter a password.
- The app produces an encrypted Base64 string. Copy it and send or store it however you like.
- Open the app and tap Decrypt.
- Paste the encrypted Base64 string.
- Enter the password that was used to encrypt it.
- The original text is revealed if the password is correct.
Important: If you forget your password, there is no way to recover the message. No one can reset or retrieve it.
| Property | Detail |
|---|---|
| Encryption algorithm | AES-256-GCM — authenticated encryption that protects confidentiality and detects tampering |
| Key derivation | PBKDF2-SHA256, 100,000 iterations — strengthens passwords against brute-force attacks |
| Salt | 16 bytes, randomly generated per encryption |
| IV / Nonce | 12 bytes, randomly generated per encryption |
| Output format | Base64-encoded blob: [16-byte salt] + [12-byte IV] + [ciphertext + GCM tag] |
| Network access | None — all operations are local and offline |
| Storage | No passwords, plaintext, or ciphertext are stored anywhere on the device |
| Clipboard | Clipboard writes are user-initiated only |
Random salt and IV per operation means the same input text with the same password will produce a different encrypted output every time, preventing pattern analysis.
EncryptionDecryptionUtilityTool/
├── app/ # Android app module
├── gradle/ # Gradle version catalog and wrapper files
├── IOS/ # iOS project notes and files
├── docs/ # Images and assets used by the web page and README
├── index.html # Main web app
├── privacy-policy.html # Web privacy policy
├── sitemap.html # HTML sitemap
├── sitemap.xml # XML sitemap
├── site.webmanifest # Web app manifest
├── build.gradle.kts # Android project build config
├── settings.gradle.kts # Android project settings
├── gradle.properties # Android/Gradle properties
├── gradlew # Gradle wrapper (Unix)
├── gradlew.bat # Gradle wrapper (Windows)
├── LICENSE # GNU General Public License v3
└── README.md
If you find this tool useful, consider supporting its development. It helps keep the project maintained and free.
You can also reach out or report issues at: encrypt.decrypt.support@hernow.net
This project is licensed under the GNU General Public License v3.0. You are free to use, modify, and distribute this software under the terms of that licence. See the LICENSE file for the full text, or visit gnu.org/licenses/gpl-3.0.
Amanda Hernow ✉️ encrypt.decrypt.support@hernow.net
© Amanda Hernow — All rights reserved where applicable. Licensed under GPL v3.