Lifetime prices rise on 19 October →
Phox Elements
IT ALREADY WORKS WITH WHAT YOU HAVE

No migration, no CSV, no weekend.

Connect an account and the first sync runs in about four minutes. Nothing is overwritten until you approve the mapping.
IF NOTHING FITS

There is an API, and it is documented properly.

REST, JSON, cursor pagination and webhooks for every object. Rate limits are published and generous, and the sandbox is free.
Auth
OAuth 2.0 or a scoped key
Webhooks
Every object, with retries
Rate limit
600 requests a minute
Sandbox
Free, no card, never expires