EMVCo merchant QR

The EMVCo QR Code Specification is the TLV-encoded format that sits underneath most national mobile-payment schemes — PIX (Brazil), PromptPay (Thailand), UPI (India), SGQR (Singapore), DuitNow (Malaysia), BPS PayNow (Singapore), and many others. Understanding the EMVCo base format means understanding a dozen regional derivatives at once.

Canonical spec: EMV QR Code Specification for Payment Systems — Merchant Presented Mode v1.1 (2020) and Consumer Presented Mode v1.1 (2020).
Encoding: TLV (Tag-Length-Value) with 2-digit tags, 2-digit lengths, variable value. CRC16-CCITT trailer for integrity.

Merchant Presented vs Consumer Presented

MPM (Merchant Presented Mode). Static or dynamic QR displayed by the merchant. Consumer scans it from their banking/wallet app and authorises the payment. 99% of real-world QR payments use MPM.
CPM (Consumer Presented Mode). Consumer's app generates a short-lived QR (typically 30–60 seconds); merchant scans it. Less common; used where consumer connectivity is unreliable (rural India pre-UPI ubiquity, some MRT/transit systems).

MPM structure

MPM payload is a flat sequence of TLV records terminated by a CRC:

Tag	Name	Length	Notes
`00`	Payload format indicator	2	Always `01`.
`01`	Point of initiation method	2	`11` static / `12` dynamic.
`02`–`51`	Merchant account information	variable	Scheme-specific. Each scheme reserves its own tag: PIX uses `26`, UPI uses `26` too, SGQR uses `51`.
`52`	Merchant Category Code (MCC)	4	ISO 18245 4-digit code. See table below.
`53`	Transaction currency	3	ISO 4217 numeric. `840`=USD, `978`=EUR, `356`=INR, `986`=BRL, `764`=THB.
`54`	Transaction amount	variable	Decimal as string. Omit for static amount-at-scan QRs.
`58`	Country code	2	ISO 3166 alpha-2.
`59`	Merchant name	variable	Max 25 chars per spec; many schemes relax this.
`60`	Merchant city	variable	Max 15 chars.
`62`	Additional data field template	variable	Bill reference, loyalty, terminal ID.
`63`	CRC	4	CRC16-CCITT over everything before this tag (including the tag itself, length 04, minus the 4-digit value).

Regional schemes that derive from EMVCo

Scheme	Country	Merchant account tag	Notes
PIX	Brazil	`26`	Brazilian Central Bank instant-payment scheme. Adds CPF/CNPJ/email/phone PIX keys as sub-TLVs under tag 26.
PromptPay	Thailand	`29` / `30`	Uses `29` for national ID / tax ID and `30` for mobile number.
UPI	India	`26`	Same EMVCo base with UPI-specific sub-TLVs (VPA, payee name).
SGQR	Singapore	`51`	Unified QR that encodes multiple payment rails (PayNow, NETS, UOB Pay) simultaneously.
DuitNow	Malaysia	`27`	PayNet's national instant payment scheme.
FPS	Hong Kong	`27`	Faster Payment System by HKICL.
JPQR	Japan	`50`	METI-backed unified Japanese QR standard.

Common MCC codes

MCC	Merchant category
`5411`	Grocery stores, supermarkets
`5812`	Eating places, restaurants
`5814`	Fast-food restaurants
`5999`	Miscellaneous retail
`7230`	Beauty / barber shops
`8011`	Doctors
`8398`	Charitable / social service organisations
`0000`	Unknown / placeholder (spec allows this)

Canonical test vectors

Case	Inputs	Expected TLV head
Static MPM, USD, no amount	`merchant=Acme Corp city=LAS VEGAS country=US currency=840 mcc=5999`	`00020101021152045999...53037405802US5909Acme Corp6009LAS VEGAS`
Dynamic MPM, EUR, amount 25.00	(same) `amount=25.00`	Starts `000201010212` (POI method 12 = dynamic), includes `540525.00`.
Restaurant bill, INR 250, MCC 5812	`merchant=Spice House city=MUMBAI country=IN currency=356 mcc=5812 amount=250`	MCC field: `52045812`. Currency: `5303356`.

Common pitfalls

CRC computed wrong. The CRC16-CCITT is over the ENTIRE payload including tag 63 and length 04 — everything up to but not including the 4-digit CRC value. Most bugs come from computing over the payload only or including the CRC value itself.
Length field is 2 digits. Even a 1-character value takes length 01. A 100-character value takes length ?? — but wait, EMVCo caps values at 99 chars because length is 2 digits. Longer values need to be split across multiple sub-TLVs.
Currency code is numeric, not alpha. USD is 840, not USD. EUR is 978. BRL is 986. ISO 4217 has both alpha-3 and numeric; EMVCo requires numeric.
Country code is alpha-2. US, IN, BR, TH. ISO 3166-1 alpha-2. Confusingly opposite to the currency-code rule.
Static vs dynamic. If you omit the amount (tag 54), use POI method 11 (static). Static QR + amount field is spec-legal but some apps reject it. Dynamic QR without amount is a spec violation.
Merchant name char limit. Per spec, 25 chars max. Some regional schemes relax this (PIX allows 25, SGQR allows 40). Hand-tune per scheme if you're targeting a specific country.
MCC 0000. The spec permits 0000 as unknown — but many acquirers reject it in settlement. Always prefer a real MCC when you have one.

Scanner compatibility

App / device	Support	Notes
Banking / wallet app	Native	Regional apps in each country (Nubank / UPI apps / TrueMoney / GrabPay) parse the EMVCo payload natively.
iOS Camera	Raw string	Not recognised as payment. User must open their banking app and scan from there.
Android Camera	Raw string	Same — not parsed.
Google Lens	Raw string	Displays decoded text.
Industrial payment terminals	Native	Modern POS scanners include EMVCo parsing in firmware for the regional scheme(s) they support.