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Novaz AuthenticatorGET

BTCBOX 2FA: how to set up an authenticator app

By the Novaz team · Updated October 29, 2026
Novaz steps checked against version 1.0.5

On this page
  1. Turn on 2FA with an authenticator app
  2. Save the QR code or secret key
  3. When BTCBOX asks for a code
  4. If BTCBOX rejects your code
  5. Changing phones
  6. If you lose your authenticator
  7. Turning 2FA off
  8. Official BTCBOX help

BTCBOX is a Japanese crypto exchange where you trade Bitcoin and other coins for yen on its website or app. It calls authenticator codes Google2段階認証 (Google two-step verification). Its help names only Google Authenticator, but the setup is a plain QR code and secret key, the same thing any authenticator app reads (BTCBOX). This guide uses Authenticator App - Novaz on iPhone. Any authenticator app works the same way.

In practice the authenticator isn't optional anymore. BTCBOX's sign-in guide, updated in October 2026, sends you to the 2FA setup screen right after your email code if you haven't set it up yet, and then on to a passkey (BTCBOX). BTCBOX requires a passkey, and you need 2FA in place before you can create one (BTCBOX).

How we checked this guide: the BTCBOX steps come from BTCBOX's own help center, mostly its Japanese pages, linked below, which we read on October 24, 2026. The pages show a browser check to automated visitors, so we read them through the help center's public article feed on support.btcbox.co.jp. We haven't tested them on a BTCBOX account, so a label may differ slightly. Japanese labels are copied as shown, with our translation in parentheses. The Novaz steps are checked against the app, version 1.0.5.

Turn on 2FA with an authenticator app

The setup happens during sign-in, not in a settings menu (BTCBOX, BTCBOX):

  1. On the BTCBOX sign-in screen, enter your email address and press パスワードでログイン (sign in with password). Enter your password and press ログイン (sign in).
  2. Enter the code BTCBOX emails you and press 確定 (confirm). The 2FA setup screen opens.
  3. BTCBOX shows a QR code and a シークレットキー (secret key). Save one of them now (see the next section).
  4. In Novaz, tap +, then Scan QR code, and point the camera at the QR code. If it's on the iPhone you're using, take a screenshot, then tap + and Choose a photo (see scanning a QR code on the same iPhone).
  5. To type the key instead, tap +, then Enter key manually. Put "BTCBOX" in Service and paste the secret key into Setup key. More in What is a 2FA setup key?
  6. Type the 6-digit code from Novaz into the field on the BTCBOX screen and press 確認 (the English help calls it Confirm).
  7. The setup is done when BTCBOX says Google２段階認証が有効です (Google two-factor authentication is enabled).

BTCBOX then moves you to the passkey screen. Its combined guide walks through both steps in one go (BTCBOX).

Save the QR code or secret key

BTCBOX recommends keeping the QR code or the secret key from the setup screen. With it, you can restore your codes after a phone change or if you delete the authenticator app by mistake. It also asks you not to let anyone else see it (BTCBOX).

The help pages don't mention backup codes. Novaz's own iCloud backup or backup file can bring BTCBOX back on a new iPhone, but if you have neither, that saved key is your backup. Store it in a password manager or on paper, away from the phone.

When BTCBOX asks for a code

Until you add a passkey, signing in with your password takes the email code and a code from your authenticator, entered on the same screen (BTCBOX). Once a passkey is set, password sign-in turns off, and BTCBOX says the old method with email, password and 2FA code can't be used anymore (BTCBOX).

The code is still asked for elsewhere. BTCBOX's guide to registering a crypto withdrawal address, from 2024, asks for a 2FA code along with an SMS code and your trading password (BTCBOX). So keep Novaz set up even after you switch to a passkey.

If BTCBOX rejects your code

BTCBOX's advice is to fix the phone's clock, since a clock that's off makes correct-looking codes fail. On iPhone: open Settings > General > Date & Time, turn on Set Automatically, then restart the iPhone (BTCBOX). Novaz also warns you when the clock is 15 seconds or more off. Other causes are in Authenticator code not working?

Changing phones

BTCBOX's phone-change page gives two cases (BTCBOX):

  • You saved the secret key: you don't need to do anything on the old phone. Set up the new phone with the same key.
  • You didn't: before you switch, turn 2FA off (below), set it up again, and save the new key this time. Delete the old BTCBOX entry from your app, since its codes stop working.

If you back up Novaz with iCloud backup or a backup file, restore it on the new iPhone and BTCBOX comes with it. Otherwise, add BTCBOX again from the saved key or QR code. See How to transfer your authenticator app to a new iPhone.

If you lose your authenticator

If you saved the secret key or QR code, add it to Novaz on your new phone and carry on. If not, BTCBOX has a self-service reset that goes through your registered phone number (BTCBOX):

  1. Click 2段階認証コードが不明になった場合はこちらへ (if you don't know your 2FA code, go here). On the website it appears once you've started signing in; in the app it's on the sign-in screen.
  2. Enter your email address and password and continue with 確認.
  3. Open the email BTCBOX sends and choose スマホでアクセス (open on phone) or PCでアクセス (open on computer).
  4. Click コード取得 (get code), enter the SMS code sent to your registered phone, and click 確定. 2FA is now off, and you can set it up again.

The app and phone-browser versions follow the same steps (BTCBOX). If you can't use that either, BTCBOX resets 2FA for you. Contact it through the request form with your date of birth and registered address. For a business account, give those of the person in charge of trading (BTCBOX). BTCBOX doesn't say how long this takes. More in Lost the phone with your authenticator app?

Turning 2FA off

Go to 設定 (settings), then 2段階認証の設定 (2FA settings). Under Google2段階認証を取消す (cancel Google two-step verification), enter your current code and click 認証取消 (cancel authentication) (BTCBOX). The 2024 phone-change page calls that section 利用の開始と停止 (start and stop use), so the wording may differ. In Novaz, open the BTCBOX entry and tap Remove account once 2FA is off.

Official BTCBOX help

More guides: Crypto exchanges and wallets