Encode and decode secret messages as musical note sequences directly in Gmail and Facebook Messenger.
Users
3
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Rating
0.0 / 5
unchanged in 30 days
Ratings
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#353K
#270K among extensions
Version
2.1.1
updated 3 Sep 2026
Users
monthly, 4 months
Latest, 15 Oct 2026:3 usersMove the mouse over the chart for any month
Ratings count
monthly, 4 months
Latest, 15 Oct 2026:0 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About Euvoli — Pass Messages in Music
EUVOLI — PASS MESSAGES IN MUSIC
Euvoli brings an entirely new kind of privacy to your email and messaging. Instead of obvious encryption that signals "something secret is here," Euvoli transforms your message into a beautiful sequence of musical notes — passing it in plain sight where no one would ever think to look.
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WHY EUVOLI IS DIFFERENT
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Every other privacy tool — Signal, PGP, encrypted email — has one fatal flaw: it's obvious. When someone sees an encrypted message, they know a secret exists. In repressive environments, that alone can be dangerous. Border agents, surveillance systems, and deep packet inspection tools are all trained to detect encryption.
Euvoli takes a completely different approach. Your message doesn't look encrypted — it looks like music data. A JSON note sequence shared in an email or message raises no flags, triggers no algorithms, and attracts no attention. The message isn't just unreadable without the key — its very existence is concealed.
This is steganography: concealing the fact that a message exists, not just its contents.
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WHAT EUVOLI DOES
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Euvoli encodes any text message as a sequence of musical note pairs using the Melography protocol — a cryptographic system where each character maps to a unique pair of musical notes through a passphrase-derived cipher.
The same letter maps to completely different notes every time it appears, making frequency analysis impossible. Without the correct passphrase, an observer cannot even locate where the message begins or ends — let alone read it.
In Gmail, Euvoli adds a simple 🎵 Encode button to your compose window. Type your message, enter a shared passphrase, click Encode & Insert — and your message becomes a stream of note data sitting quietly in your email. When your recipient opens the email, a 🎵 Decode Euvoli Message button appears automatically. They enter the passphrase and read your original message.
In Facebook Messenger, Euvoli adds a 🎵 button directly in the message toolbar alongside the native emoji, photo, and GIF buttons. Encode any message before sending it. Recipients see a Decode Euvoli Message option in the three-dot menu on any received Euvoli message.
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HOW IT WORKS — THE MELOGRAPHY PROTOCOL ─────────────────────────────────────────
Melography is a deterministic bidirectional mapping system that converts text into musical note pairs:
96 printable characters mapped to 130 unique note pairs
Each character uses TWO musical notes — creating rich musical intervals
Polyalphabetic cipher: same character → different notes every time
Passphrase feeds into PBKDF2 key derivation → ChaCha20 stream cipher
Each character position gets a unique cryptographic offset
Message boundaries are concealed — without the key, you cannot find where the message starts or ends
Steganographic padding before and after the message conceals its length
The note sequence sounds like real music when played back
The result is a system where:
✓ Content is protected — unreadable without the passphrase
✓ Existence is concealed — message boundaries unlocatable without the passphrase
✓ Length is concealed — padding obscures how long the message is
✓ Frequency analysis is defeated — polyalphabetic mapping
✓ No dedicated infrastructure needed — works over any platform
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FEATURES
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✦ ONE-CLICK ENCODING IN GMAIL Click the 🎵 Encode button in any Gmail compose window. Type your message, enter your shared passphrase, choose to insert as text or download as a file. That's it.
✦ FACEBOOK MESSENGER SUPPORT A 🎵 Euvoli button sits naturally in the Messenger toolbar alongside emoji, photo, and GIF buttons. Works in both the full Messenger page and the modal chat window. Decode option appears in the three-dot menu on received Euvoli messages.
✦ AUTOMATIC DECODE DETECTION When you receive an email containing an Euvoli note sequence, a 🎵 Decode Euvoli Message button appears automatically at the top of the email. Enter the passphrase to reveal the message instantly.
✦ LOCAL ENCODING — YOUR MESSAGE NEVER LEAVES YOUR DEVICE All encoding and decoding happens in your browser. Your plaintext message is never transmitted to any server. The passphrase never leaves your device. Only the encoded note sequence — which is meaningless without the key — is inserted into your email or message.
✦ PASSPHRASE PROTECTION Share a passphrase with your recipient through any channel — a phone call, in person, a previous message. Once established, all future communication using that passphrase is protected.
✦ TRANSPORT AGNOSTIC The encoded note sequence is just text — it works over any platform that can carry text or files. Email, messaging apps, social media posts, SMS. If you can send text, you can send an Euvoli message.
✦ MUSICALLY AUTHENTIC The note sequences are designed to sound like real music when played back. The Euvoli web app at euvoli.qizhonglabs.com lets you hear your encoded message played on piano, strings, music box, harp, or brass.
✦ NO ACCOUNT REQUIRED Install and start encoding immediately. No sign-up, no account, no personal information required.
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WHO EUVOLI IS FOR
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JOURNALISTS AND ACTIVISTS Communicating in environments where encryption is detected, flagged, or illegal. Euvoli messages pass through surveillance systems as ordinary data files. No Euvoli-specific traffic pattern exists to block or detect.
PRIVACY-CONSCIOUS INDIVIDUALS Anyone who wants genuine privacy without the social signal that comes with obvious encryption. Your communication looks completely ordinary.
HUMAN RIGHTS DEFENDERS Operating in regions where encrypted communication attracts unwanted attention. Eu…