Nmail is a free, open-source email client built on the Nostr protocol. It is designed for people who want an email identity they control, rather than one tied to a large provider that can scan messages, serve ads or close the account. If you already use Nostr or are curious about decentralized communication, Nmail gives you a familiar inbox-style interface on top of that network.
The core idea is simple: your address is an identity you hold, not a mailbox rented from a company. Messages sent between Nmail users are locked so that only the sender and recipient can read them. The program is written in Dart with Flutter, which is why the same codebase can target several platforms. The latest release is v0.19.1, and the source code is publicly available on GitHub.
What Is Nmail and How Does It Differ From Gmail?
Traditional email providers hold your mailbox on their servers and set the rules for it. Nmail works differently. Your identity is a cryptographic key pair from the Nostr protocol, and messages are relayed through independent servers rather than one company's infrastructure.
The practical difference shows up when something goes wrong. With a conventional account, a suspended login can lock you out of years of correspondence. With a Nostr identity, the keys you hold are the account, so no provider can close it on your behalf.
This does not make Nmail a replacement for every email use case. Its strengths are privacy and ownership, and some conventional tools, such as calendar integrations and large-scale mailing lists, are simply not part of its scope.
Who Is Nmail For?
Nmail suits a few clear groups of people. Privacy-minded users who are tired of advertising and data collection will find the design appealing. Nostr users who already have a public key will get a mail interface that fits the identity they use elsewhere.
Developers and open-source enthusiasts may also be interested, since the codebase is public and written in Flutter, which makes it a readable reference for cross-platform apps built on a decentralized protocol.
People who need guaranteed support, a long track record of stability or a large contact network across established providers may find the ecosystem still smaller than they would like. It is worth testing with a secondary address before moving anything important.
How Encrypted Nostr Messaging Works
Nostr is a protocol in which clients publish signed events to relay servers. Anyone can run a relay, and a user can connect to several at once. Because each event is signed with the author's private key, recipients can verify who wrote it.
Encryption adds a second layer. The message content is locked with keys derived from the sender and recipient identities, so relay operators can see that traffic exists but cannot read what it says. Understanding this split helps explain why metadata, such as who talks to whom, can still be visible even when the text is private.
For a non-technical user, the main takeaway is that your keys are the most important thing you own in this system. Losing them means losing access to your identity, which is why careful backup matters more here than with a standard password reset flow.
Getting the Most Out of a Decentralized Inbox
Using a Nostr-based mail client well requires a slightly different mindset. Consider using a separate identity for sensitive correspondence, and keep a secure, offline copy of your keys. Think about which relays you trust, because they handle the delivery of your messages.
For everyday use, sending an encrypted message to another Nmail user is the cleanest experience. Messages to traditional addresses work too, but they are not protected in the same way, since the recipient's ordinary mail server handles them. Set expectations with contacts before you rely on the app for anything time-sensitive.
Key features
Self-Owned Identity
Automatic Encryption
Mail to Traditional Addresses
No Tracking or Ads
Offline Caching
Supported coins
Nmail is built around the Nostr network. Its documentation refers to Nostr as the underlying network for identities and encrypted messaging, and the app is designed to work with that ecosystem rather than with cryptocurrency assets.
How to install Nmail on Windows
- 1
Download the Program
Get the Windows build from the official project page or from the GitHub Releases page of the repository, where the source code and release artifacts are published. Avoid copies on random download sites.
- 2
Verify the File
Before running the installer, compare the SHA-256 checksum of the downloaded file against the value published with the release. If the project provides a signature, verify it as well. A mismatch means you should not run the file.
- 3
Run the Installer
Launch the installer and follow the prompts. Windows may show a SmartScreen warning for software that is not widely distributed; confirm the checksum first, then decide whether to continue.
-
Create or Import Your Identity
On first launch, set up your Nostr identity. Store the generated keys in a password manager or an offline location immediately, because they are needed to recover your account.
System requirements
- A 64-bit version of Windows that supports the release build
- Enough free disk space for the app and locally cached messages
- A stable internet connection to reach Nostr relays
How to use Nmail
Nmail is straightforward once your identity is set up. The steps below walk through the basic workflow for a first session.
- Open Nmail and sign in with the identity you created or imported.
- Wait for the app to connect to relays and load your existing messages.
- Select compose, then enter the recipient's Nostr public key or, for an ordinary address, the email address.
- Write your message and send it. Encrypted messages to Nostr users are locked automatically.
- Check the inbox for replies, which arrive through the relays you are connected to.
- Review your settings to confirm which relays the app uses, and adjust them if you want more control over delivery.
- Back up your keys again after any major change to your identity.
Pros & cons
- Free and open-source, with public source code on GitHub
- Automatic encryption for messages between Nmail users
- Identity you control rather than a provider-held account
- No ads or trackers in the inbox
- Can reach traditional email addresses as well
- Ecosystem is smaller than established email networks
- Losing your keys means losing access to your identity
- Metadata on relays can still reveal who communicates with whom
- Mail to ordinary addresses is not end-to-end encrypted
- Still a young project at version v0.19.1, so expect rough edges
Is Nmail safe?
Nmail is open source, which lets you inspect how it works. Download it only from the official project page or the GitHub Releases page, and verify the SHA-256 checksum before installing. If the release is signed, check the signature as well.
Never enter your private key or seed-style recovery phrase on a third-party website or in a message from someone claiming to be support. Anyone who obtains your private key can impersonate your identity, so store it in a password manager or an offline medium.
Keep in mind that the project is actively developed, with a recent code update, but it is still at an early version number. Read the release notes before each update, and test with a secondary identity if your correspondence is important.
- Official source only. Download from github.com/nogringo/nostr-mail-client. Ignore ads and lookalike domains.
- Check the SHA-256. Compare the installer hash with the value the developer publishes before running it.
- Never share your seed phrase. No developer, support agent or website — including CryptApps — will ever ask for it.
Alternatives
Several other Nostr clients are listed in this catalog, and they serve different purposes. Amethyst and Coop focus on social and personal messaging, while Gossip is a desktop client written in Rust. Nmail is distinct because it treats the Nostr identity as an email-style inbox, including delivery to traditional addresses.
Tools such as NAK and Nostr Commander RS are command-line oriented, which suits developers and power users but is less approachable for everyday email. Vega offers a cross-platform desktop experience for general Nostr use. If your main goal is mail-like communication, Nmail is the closest fit; if you want a broader social client, one of the others may serve you better.
Specifications
- Price
- Free
- Type
- Open source
- License
- —
- Latest version
- v0.19.1
- Last update
- 30 Oct 2026
- Windows support
- Yes (Windows build or installer)
- Source code
- github.com/nogringo/nostr-mail-client
Frequently asked questions
Yes. Nmail is free and open source, and its source code is available on GitHub. There are no subscription fees for the basic client, so you can try it without paying anything.
It can be, provided you download it only from the official project page or GitHub Releases, verify the SHA-256 checksum, and keep your private keys private. The open source code lets you review how the app works.
Nmail is built on Nostr, so you will need a Nostr identity, which the app can help you create. Your keys are the core of the account, so back them up carefully as soon as you set them up.
Yes, Nmail can reach traditional email addresses. However, those messages are not protected by the same encryption as messages between Nmail users, because the recipient's ordinary mail provider handles them.
You lose access to that Nostr identity, and there is no central support team that can reset it for you. This is why storing a backup in a password manager or offline medium is essential before you rely on the account.
It stores messages locally, so previously loaded mail remains available without a connection. Sending and receiving new messages does require an internet connection to reach relays.
The project is built with Flutter and supports Linux, Android and web. The Windows build is available from the official download sources, so you can use it on a desktop without a separate browser setup.
Not exactly. Nmail focuses on email-style messaging, while social clients focus on public posts and feeds. Both use the Nostr protocol, but they present it in different ways.
Verdict
Nmail suits privacy-conscious users, Nostr enthusiasts and developers who want an email-style client on a decentralized network. It is free, open source and ad-free, and it gives you an identity you control. Its ecosystem is still developing, so it works best as a secondary or experimental tool for now. Check the latest version on the official website before installing, and back up your keys before you start.