gpg4o vs Lockbin

gpg4o is a Microsoft Outlook add-in for encrypting, decrypting, signing, and checking messages and attachments. It uses public and private keys under the OpenPGP standard, and supports encrypted HTML email, PGP/MIME, and PGP/Inline. Its key management can synchronize keys, use local or public key servers, and check the Web of Trust; central management requires Enterprise KeyServer. The product also supports terminal servers, Microsoft Policy Manager, automatic key generation, and working groups. When encryption is enabled, it protects message text and attachments, but not the subject line or recipient list. The current feature page lists Outlook 2024 or 365 Classic on Windows 11 and marks Mac OS unsupported. A limited free version is available without a time limit, and a 180-day trial is noted. The listed gpg4o plan costs €99.95 a month. After maintenance expires, users can still send and read encrypted or signed email, but they do not receive further updates.

Lockbin is a web application for sending private email messages and files. Recipients can open a message using a unique URL and password; passwordless secure links are also available for known recipients. Messages use TLS in transit and FIPS 140-2 verified AES-256 encryption at rest. Decryption keys are held by the sender and recipient rather than stored in plaintext on Lockbin servers. It works in Chrome, Firefox, Safari, or Edge without a download or installation, and is listed for Linux, macOS, web, and Windows. Lockbin works alongside Google Workspace and Microsoft 365 without a plugin or extension. Premium users can create file-drop links or secure forms to receive files without requiring an account or password. The free plan covers one user, 25 MB attachments, and six months of inbox storage; the site also advertises 10 free messages with no credit card required. Premium costs $10 per user per month. Uncollected messages are destroyed after six months, and read files not marked for deletion are removed within 24 hours.