If you've spent time outside China while keeping a life inside it, you know the problem. Your bank, 支付宝, 微信, and most government services are still tied to a Chinese phone number — and that number lives on a SIM card sitting in a drawer back home. The verification code arrives on a phone you're not holding, in a country you're not in, and it expires in a couple of minutes. OTPBase exists to close that gap: forward the code off the home phone and read it from wherever you are.
Why the SIM is the real key
A Chinese phone number isn't just one login factor among many. For banking, 支付宝, 微信, and a lot of official services, it's the anchor the whole account hangs on. You can't easily move it abroad, roaming is unreliable for SMS, and swapping it out can lock you out of the things that needed it in the first place. So the SIM stays home — and the codes stay with it.
The codes also don't wait. A bank OTP that's good for ninety seconds is useless if you find out about it an hour later. The goal is simple: get the code from the home phone to your eyes fast enough to actually use it.
The setup, end to end
The shape of it is: the phone that holds the SIM forwards incoming SMS into OTPBase, and you read the result anywhere.
- Pair the home phone. Sign in and go to
/devices, choose "Pair new device," and you'll get an 8-character pairing code. The phone holding the SIM exchanges that for a one-time device token. From then on, that phone is a trusted forwarder. - Forward incoming SMS. On iOS, an Automation in the Shortcuts app can fire whenever a message arrives and POST it to OTPBase. On Android, an SMS-forwarder app does the same. Either way, each incoming text gets handed to OTPBase with the device token.
- Read the code. Open OTPBase in any browser and the latest code is on the page. Or, if you're scripting a login, pull it from the read API.
The parser recognizes the major Chinese banks and apps — 支付宝, 微信, and the big banks — out of the box, so it pulls the actual code out of the message text instead of making you squint at a forwarded SMS.
Privacy: forward less, keep less
Forwarding texts off your phone deserves a careful eye, so here's how OTPBase keeps the footprint small.
- Filter at the source. You decide which messages the Shortcut or forwarder sends. Set it to forward only OTP-style texts and leave the rest — balance alerts, transaction notices, personal messages — sitting on the phone where they started. The codes you need cross the wire; the noise doesn't.
- Encrypted, then gone. Codes are encrypted at rest with AES-256-GCM. A code is visible for fifteen minutes, then hidden, and the underlying record is physically deleted within the hour, with no backup keeping it. There's no growing archive of your bank's messages building up somewhere.
- Optional view password. Turn one on and decryption happens only in your browser, so the server holds ciphertext it can't read.
In practice
Once it's running, it fades into the background. A 支付宝 code arrives on the home SIM, the phone forwards it, and a second later it's on your screen in another time zone — parsed, ready to copy, and gone within the hour. The SIM never has to leave the drawer, and you stop missing codes you were never in the room to receive.