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View Key Pair Details

The Key Details window shows everything about a key: who it belongs to, its primary key and subkeys, the signatures on it, and the actions you can take.

To open it, right-click a key in the Key Toolbox or the Key Management window and choose Show Key Details. Double-clicking a key also opens this window.

This part of the window helps you manage the key. Here is what each piece means.

Who the key belongs to. This isn’t fixed: you can change it by creating a new UID in the UID section and setting it as the primary UID. OpenPGP splits this into Name, Email, and Comment.

The primary key is the heart of the key pair. Without its private part you can’t do management tasks like adding or revoking subkeys, much like not being able to open the keyring. To learn more, see Fundamental Concepts.

A “missing” primary key means the private part of the primary key is absent, not that the whole key is gone. Remember: the primary key and every subkey is itself a pair of a public and a private key.

A short, unique ID for the key, fixed when the key is made. This is the primary key’s ID. It is shorter and easier to read than the fingerprint.

The algorithm the primary key was made with. It decides what the key can do. For example, RSA can encrypt and sign, while DSA can only sign. Modern elliptic-curve algorithms like ECDH (for key exchange) and ECDSA (for signatures) give strong security with shorter keys.

Shows the key type and length together, and is sometimes more exact than the Algorithm field, naming the specific method such as ED25519 or NISTP256.

The length of the primary key. Longer keys are harder to break but slower to use. For RSA, 2048 bits is generally safe enough.

What the key pair can do, combining the abilities of the primary key and all subkeys. The possible abilities are Certify, Encrypt, Sign, and Auth. For example, if any subkey can sign, Sign is listed here.

How much you trust this key’s owner to correctly verify and sign other keys, part of the web-of-trust model. This field is shown only when the active engine reports owner trust (GnuPG); engines that don’t support it hide the field.

When the primary key was made, shown in your local time.

When the primary key expires. After that it can’t be used for any operation, and its subkeys stop working too. You can change the expiration time whenever you like, or set it to never expire, as long as the primary key’s private part exists.

Which key format the primary key uses, shown as v4, v5, or v6.

  • v4 is the widely compatible default, from the older OpenPGP standard.
  • v6 is the format from the current OpenPGP standard, RFC 9580. Post-quantum keys need it.
  • v5 is the format from LibrePGP, a separate standard that split off from OpenPGP. GnuPG 2.5 and later can make and use v5 keys.

The two standards are not compatible with each other. A v5 key works with GnuPG and other LibrePGP tools, and a v6 key works with RFC 9580 tools. Many tools support only one of the two.

When the key pair’s content last changed. Adding a UID or subkey counts as a change.

Whether the primary key’s actual content is present, shown as Exists or Not Exists. If it is missing but the key pair still has usable subkeys, you can keep using the key for normal tasks. You just can’t change its content (no adding UIDs or subkeys) or use it to sign other keys.

The fingerprint is a unique code people use to quickly check that a key is the one they expect. It is unique for every key in the world. (You can also compare the Key ID above.) This is the primary key’s fingerprint.

A User ID (UID) is the label that says who a key belongs to, like a name tag on a keyring. It gives you a rough idea whether a key is the one you expect, but for sure identification you should compare fingerprints or key IDs. A key can have several UIDs, but only one primary UID, which is always shown first.

View Key Pair Details UID

Each UID has three parts: Name, Email, and Comment. The name should be at least five characters and the email must be a valid format; comments are flexible.

The lower part of the window shows the signatures on the selected UID (the one you clicked, not the one ticked). Signatures are how trust is built: when someone receives your public key, they can sign your UID with their key to vouch for it, then share the signed key on a key server. The more people who do this, the more trustworthy the key looks.

You can also sign a UID with the primary key of another key pair. A primary UID with many valid signatures is generally seen as more trustworthy.

Some signatures may not show the signer’s UID, as in the image above. To identify them, import the matching key from another source, such as a key server. The Key ID is shown, which helps you find and import the right key.

Subkeys are a core GnuPG feature that improves both security and flexibility. They can feel complex at first, so here are the basics:

  • Keyring model: think of your key pair as a keyring, with one primary key and zero or more subkeys.
  • Primary key vs subkeys: the primary key is the root of trust. It certifies subkeys and is kept for critical actions like signing other keys or adding UIDs.
  • Daily work: subkeys handle tasks like signing and encryption, even when the primary key is absent or unavailable.
  • Overlap: if two subkeys can both sign, the earlier one is used.
  • More algorithms: subkeys can use more algorithms than the primary key, but for daily use the effect is the same.
  • Security isolation: if a subkey is compromised, you revoke just that one and the trust anchored by the primary key stays intact. But if the primary key is compromised, the whole key structure is at risk.

The Key Details window lists the primary key and all subkeys with their properties (algorithm, size, usage, and so on), so you can manage them at a glance.

Shows whether a (sub)key’s private part has been moved to a hardware smart card.

  • When a key is moved to a smart card, its private part is physically transferred to the card and removed from your local key database.
  • This can’t be undone. The private key now lives only on the card and can’t be pulled back.
  • It is strong protection against malware and key theft: using that key to sign or decrypt now needs the card present and unlocked.

Right-click a subkey in the list for actions that apply to just that one:

  • Change Passphrase: set a new passphrase for this subkey alone, leaving the others as they are. New in v2.2.2.
  • Move to Card: move this subkey onto a smart card. See OpenPGP Smart Cards.
  • Set Expiry: give this subkey its own expiry date.

What you can do here depends on whether the key pair has only a public key, or a private key too.

These are the actions available for a public key.

Saves the public key to a file, ready to share with others, upload to a key server, or back up.

A dropdown for working with key servers (a place where public keys are stored and shared). For example, you can refresh your copy of the public key with updates from the server.

Sets how much you trust this key’s owner to correctly verify and sign other keys, part of the web-of-trust model. This affects how your system judges the signatures that owner makes.

When the key pair includes a private key, you get more actions, covering both the public and private parts.

Saves the public key to a file, for sharing, uploading to a key server, or backup.

Exports the private key. There are usually two modes:

  • Export Complete Private Key: the entire private key with all its information. Use this for a full backup or to move the key to another system.
  • Export Minimal Private Key: only the essential parts, with less data. Useful for more secure transfers or environments with strict requirements.

Changes the expiration date and time of the primary key. This helps you manage the key’s lifecycle and keep it valid for as long as you need.

Changes the password that protects the private key. Worth doing if you think the current one may be exposed, or as part of regular good habits.

A dropdown for working with key servers using the public key, such as uploading it or refreshing it from the server.

A dropdown to create a revocation certificate for the key, or import an existing one. Revoke a key if it is compromised or no longer needed: this marks it invalid so it can’t be misused. The revocation is usually uploaded to a key server so others learn the key is revoked.