Use the web decoder

Step 01

Start with a payment request

Paste a complete BOLT11 invoice into the decoder. If you copied it from Polar’s JSON, use only the payment_request value. You can also choose a sample or import a QR image.

A mainnet invoice starts with lnbc. Testnet uses lntb, signet uses lntbs, and regtest uses lnbcrt. A payment hash, Lightning address, or entire JSON response is not a BOLT11 invoice.

Step 02

Decode and inspect

Optionally choose an expected network, then select Decode invoice. The summary shows the requested amount, description, and detected network. The validity card shows the signature, creation time, and expiry.

The validation report follows the summary. Payment identifiers have copy buttons, and Advanced details contains fallback addresses, description hash, CLTV delta, and route hints.

Step 03

Export or start again

Select Export JSON to download all decoded fields and the validation report. Select Decode another invoice to return to the input.

The built-in samples are expired public examples. Their expiry warnings are expected. Decoding does not make a payment.

Step 04

How the web app connects

QR images are read in your browser. Only the extracted invoice text is sent to the configured Rust API when you decode. The web app needs an available API; use the terminal client for fully offline decoding.