2FA guides
Plain-language guides, updated 21 September 2026.
Short, practical guides about two-factor authentication: how the codes work, how to keep them safe, and how to move them between apps without locking yourself out. Everything here describes what KeyNesta does today, not what is planned.
Set up 2FA on a service
- How to set up 2FA with an authenticator appFourteen services, from Google and GitHub to AWS and Discord, each checked against its own help page.
- Set up 2FA on GoogleGoogle Account, Security, 2-Step Verification, and the backup codes to download.
- Set up 2FA on GitHubSettings, Password and authentication, and the recovery codes GitHub makes you save.
- Set up 2FA on AWSTwo consecutive codes, the secret key, and up to eight MFA devices.
Every service: Google, Microsoft, GitHub, AWS, Amazon, Facebook, Instagram, X, Discord, Dropbox, Coinbase, PayPal, LinkedIn, Reddit.
Moving to a new phone
- Move your authenticator to a new phoneGoogle Authenticator, Microsoft Authenticator, Authy, 2FAS and Aegis, and what to do if the old phone is gone.
- Move Authy to a new phoneMulti-device, the phone number you registered with, and the backup password nobody can reset.
- Move Google Authenticator to a new phoneSign in to sync, or Transfer accounts with a QR code.
Every app: Google Authenticator, Microsoft Authenticator, Authy, 2FAS, Aegis.
Switching and importing
- Import from Google AuthenticatorUse the transfer QR to move every code in about five minutes, decoded on your device.
- Import from Aegis and 2FASExport an unencrypted backup, paste or upload it, review the preview, delete the file.
- Google Authenticator alternativeWhat changes when backups are files you own and the app runs in a browser.
- Authy alternativeAuthy has no export, so leaving is manual. Here is the dependable route.
- How to export Authy codes in 2026Why there is no export, which workarounds are myths, and the route that actually moves every token.
- An Authy desktop alternativeTwilio retired the desktop apps in 2024. What is left if you want codes on the computer you work on.
Keeping codes safe
- 2FA backup and syncEncrypted backup files, zero-knowledge sync, and the step-by-step for a new phone.
- Web authenticatorA full authenticator in the browser, and how the vault stays private there.
- Lost phone recoveryRestore from sync or a backup, and what to do for the accounts you had neither for.
- How KeyNesta encrypts your 2FA codesAES-256-GCM, scrypt, zero-knowledge sync, and the known limits, in plain language.
- What the server storesEvery record the sync database keeps for an account, field by field, and what the server cannot read.
- ChangelogDated, user-visible changes, each tied to the commit that landed it.
- Encryption architectureThe technical version: scrypt parameters, per-object AAD, the sync protocol, the threat model.
How it works
- TOTP vs HOTPWhat the QR secret is, how a six-digit code is computed, and why it works offline.
From the blog
- Authenticator app vs SMSWhat SIM swapping changes, what an app does not fix, and how to move accounts off texted codes.
- 2FA codes in your password manager?The one-basket trade-off argued both ways, and which accounts to keep separate.
- Passkeys vs authenticator appsWhy passkeys stop phishing, and why most accounts still need TOTP.
- Authenticator app vs hardware security keyWhat a key does that an app cannot, what it costs once you buy the spare, and which accounts earn one.
- Where to store your 2FA backup codesThe storage options ranked, what to do the moment you spend one, and how to regenerate a set.
- 2FA code not workingThe clock first, then the six causes that survive a correct clock, then the way back in.
- What zero-knowledge costs youWhy we cannot read your codes, and why that means we cannot recover them either.
About the app
- FeaturesEverything KeyNesta does today, and a plain list of what it does not do yet.
- For many accountsVaults, spaces, nested groups and tags, at the scale where a flat list gives up.
- An authenticator app with folders and groupsThe short read: what folders, groups and separate vaults look like at a few hundred codes.
- For developers and sysadminsNon-default TOTP parameters, client separation, bulk import, and the missing pieces.
- PricingWhat is free forever, what is free during launch, and what Premium would add.
Where KeyNesta runs
- KeyNesta for webThe complete product in any browser, no install and no sign-up. Live today.
- KeyNesta for iPhoneBuilt, awaiting App Store release. What it adds, and what to use meanwhile.
- KeyNesta for AndroidBuilt, awaiting Play Store release. Includes the email-only sign-in limit.
From the blog
Longer pieces on why the app works the way it does, rather than how to use it.
- What zero-knowledge actually means, and what it costs youWhy we cannot read your codes, why we therefore cannot recover them, and the trade that makes.
- All blog postsNotes on how KeyNesta works and the decisions behind it.