Migrating from V1 to V2

Generate an Ed25519 key pair — see Get set up: keys & onboarding
Send your public key to Onramper support
Test V2 signing in staging
- Widget: https://buy.onramper.dev
- API: https://api-stg.onramper.com
- Use your test API key (pk_test_...) and verify signatures are accepted
Deploy V2 to production
Notify Onramper when ready — V1 will then be disabled for your account

	V1	V2
Algorithm	HMAC-SHA256 with shared secret	Ed25519 with your private key
Signature location	`signature` query param / body field	`sigV2` param (widget) or `x-onramper-signature` header (API)
Content signed	Sensitive params only, unencoded	8-line canonical string, URL-encoded query
Replay protection	None	Nonce + timestamp, 15-min window

⚠️
Encoding changed: V1 signed unencoded values; V2 signs the URL-encoded canonical query. Don't reuse V1 string-building code.