> ## Documentation Index
> Fetch the complete documentation index at: https://docs.bleepay.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Voucher Modes

> Numeric vs alphanumeric voucher formats and when each is used.

The Bleepay system supports two voucher modes to balance **compatibility** with existing terminals and **scalability** in digital environments.

## Numeric mode

* **Format**: Short sequence of **digits** (e.g. 6 digits).
* **Use case**: Compatible with legacy POS devices and keypads that accept only numeric input (e.g. ISO/IEC 7812-1, ANSI X4.13).
* **Examples**: Countertop payment terminals, integrated POS, kiosks, ATMs, older keypad-based merchant terminals.
* **Transmission**: User can read the code aloud or enter it manually; works in low-tech retail environments.

## Alphanumeric mode

* **Format**: Short sequence of **letters and digits** (e.g. 6 alphanumeric characters).
* **Use case**: Modern interfaces that support full keyboard or alphanumeric entry.
* **Benefits**: Larger space of unique codes in parallel → better scalability and lower code-collision risk.
* **Examples**: Touchscreen POS, smart POS, merchant web/mobile dashboards, self-checkout kiosks with software keypads.

## Mode selection

Mode can be chosen **dynamically** based on:

* Terminal capabilities
* Merchant configuration
* User or context preference

When the payee uses a numeric-only terminal, the payer's wallet can generate a **numeric** voucher. When the interface supports alphanumeric input, the wallet can generate an **alphanumeric** voucher for higher throughput and security.

Supporting both keeps **interoperability** with legacy hardware while allowing **high-volume** operation in modern setups.

## Next steps

* [Terminology](/home/reference/terminology) — voucher, voucher code, session.
* [Protocol flow](/home/reference/protocol-flow) — where the voucher is generated and redeemed.