What is Encrypt & Decrypt Text?
Encrypt & Decrypt Text is a free, browser-based tool in the Security & Crypto Tools suite. Encrypt text with AES-GCM 256 using a passphrase-derived key (PBKDF2, 100k iterations). Output is base64 of salt+iv+ciphertext. Decrypt with the same passphrase. 100% client-side.
The headline benefit: aes-gcm 256 encryption with a passphrase — round-trip in your browser.
Unlike most online tools that upload your file to a server, process it, and send it back, Encrypt & Decrypt Text runs entirely in your browser. Open DevTools → Network while using it and you'll see zero file-upload requests — only static assets (JavaScript, CSS, fonts) load. Your data never leaves your device.
Why use this encrypt & decrypt text?
Three reasons EasyFileKit's Encrypt & Decrypt Text stands out from the crowd:
- **Private by design** — all processing happens locally via JavaScript and WebAssembly. No server ever sees your input.
- **Instant** — no upload wait, no queue, no server round-trip. Results appear the moment you act.
- **Free & unlimited** — no accounts, no watermarks, no daily caps. Use it as many times as you like.
How to use Encrypt & Decrypt Text — step by step
Here's the complete walkthrough. Everything happens instantly in your browser:
- **Step 1.** Pick the Encrypt tab and type your secret message.
- **Step 2.** Enter a strong passphrase — it's the only key to your data.
- **Step 3.** Click “Encrypt text” to get a base64 ciphertext.
- **Step 4.** Share the ciphertext; the recipient pastes it in the Decrypt tab with the same passphrase.
That's it. No sign-up, no upload bar, no waiting. If something doesn't work as expected, check the FAQ below.
Common use cases for Encrypt & Decrypt Text
People reach for Encrypt & Decrypt Text in a few recurring situations:
- When you need the result **now** and can't wait for a server-based tool to upload, queue, and process your file.
- When your file is **private or sensitive** — financial documents, personal photos, medical PDFs — and you don't want it travelling across the internet.
- When you're on a **slow or metered connection** — uploading a 50 MB file just to compress it makes no sense when the same work can happen locally.
- When you've hit the **daily limit or paywall** on another "free" tool site.
Privacy: what actually happens to your data
This is the single most important point about Encrypt & Decrypt Text, so it deserves its own section.
When you use this tool, your input is processed by JavaScript running in your browser tab. The code is downloaded once (cached afterwards) and executes locally on your CPU. At no point is your file, your text, or your input data transmitted to any server.
You can verify this yourself in under 30 seconds:
- Open Encrypt & Decrypt Text in your browser.
- Press F12 to open DevTools.
- Switch to the Network tab and tick "Disable cache".
- Use the tool — drop a file, type text, whatever the tool needs.
- Watch the Network log. You'll see only static assets (JS, CSS, fonts, icons). No request contains your data.
This isn't a setting you toggle or a promise in a privacy policy — it's how the tool is architecturally built. There is no upload endpoint to call.
Frequently asked questions about Encrypt & Decrypt Text
Q: What encryption algorithm is used?
A: AES-GCM with a 256-bit key, the same authenticated encryption used by TLS and modern disk encryption. GCM mode adds an authentication tag so tampered ciphertext is rejected.
Q: How is the key derived from my passphrase?
A: PBKDF2 with SHA-256 and 100,000 iterations, using a fresh 16-byte random salt per encryption. That slows brute-force attacks on weak passphrases by orders of magnitude.
Q: What's inside the base64 output?
A: salt(16 bytes) | iv(12 bytes) | ciphertext + auth tag. The salt and IV are stored alongside the ciphertext so decryption only needs the passphrase.
Q: What happens if I use the wrong passphrase?
A: AES-GCM authentication fails and the tool reports a clear “wrong passphrase or corrupted input” error. The plaintext is never revealed on a failed attempt.
Q: Is this suitable for storing secrets long-term?
A: Yes for moderate-sensitivity data. For high-value secrets, use a dedicated password manager or full-disk encryption — those add hardware-backed key storage and stronger KDFs (Argon2, scrypt).
Q: Is my text or passphrase uploaded?
A: Never. Encryption and decryption happen entirely in your browser via the Web Crypto API. No server is involved.
Encrypt & Decrypt Text: EasyFileKit vs server-based tools
Most "free" online tools that do what Encrypt & Decrypt Text does follow the same model: you upload your file to their server, they process it with a backend script, then they send the result back. Here's the honest comparison:
| | EasyFileKit | Server-based tools |
|---|---|---|
| **Your file leaves your device?** | Never | Yes, uploaded to a server |
| **Speed** | Instant (no upload) | Slower (upload + queue + download) |
| **Privacy** | Complete | Your file is on someone else's computer |
| **Cost** | Free, unlimited | Often capped or "premium" gated |
| **Works offline** | Yes (PWA) | No |
Server-based tools aren't evil — they exist because some tasks genuinely need heavy backend compute. But for everything Encrypt & Decrypt Text does, client-side processing is strictly better for you.
Under the hood: how Encrypt & Decrypt Text works
Encrypt & Decrypt Text is built with modern browser APIs. Depending on what it does, it may use:
- **Canvas API** — for image manipulation (pixel-level access, filters, resizing).
- **Web Crypto API** — native, hardware-accelerated cryptography (AES-GCM, SHA-256, PBKDF2) for any encryption or hashing.
- **pdf-lib / pdf.js** — fully client-side PDF creation and rendering.
- **MediaRecorder API** — for capturing screen, audio, and video.
- **WebAssembly** — for heavy codecs (image compression, media processing).
All of these run inside your browser's sandbox. They cannot access your filesystem (beyond files you explicitly choose), cannot make network requests with your data, and cannot run persistently in the background.
Pro tips for getting the most out of Encrypt & Decrypt Text
- **Bookmark the tool** — it works offline once cached, so you can use it even without a connection.
- **Install EasyFileKit as a PWA** — open the browser menu and choose "Install app" for a standalone window and offline access.
- **Use it on mobile** — every tool is fully responsive and works on phones and tablets, not just desktops.
- **No file size anxiety** — because nothing uploads, you can process large files that server-based tools would reject or charge for.
Try Encrypt & Decrypt Text now
The tool is right above this article — scroll up and start using it. No sign-up, no upload, no limits.
If you found Encrypt & Decrypt Text useful, explore the rest of the Security & Crypto Tools suite — there are more tools that work the same private, instant, free way. And if you have a question that isn't covered in the FAQ above, the About page has our contact email.