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Zeller website screenshot

Zeller

Zeller is a Melbourne-founded Australian payments and business banking company (founded 2020 by former Square Australia executives Ben Pfisterer and Dominic Yap) that gives SMEs an integrated stack of card payment acceptance, a transaction account, a Mastercard debit card, and financial management tools in one place. As a merchant acquirer it processes in-person and online card payments (Visa, Mastercard, eftpos, American Express, JCB, Apple Pay, Google Wallet) across its Zeller Terminal hardware, Tap to Pay on mobile, and online checkout, positioning itself against Square and fellow ASX-adjacent acquirer Tyro. Zeller reached unicorn status on a 2022 Series B. Its API posture is developer-account-gated: the Zeller Developer Suite ships Payments SDKs (React, React Native, Windows .NET, Android, iOS) plus Terminal, Online, and Tap to Pay integration APIs, with reference documentation unlocked only after creating a free developer account. The developer portal authenticates through an Auth0 (OAuth2 / OpenID Connect) tenant; no OpenAPI specification is published for anonymous download.

agent aware

Limited machine-readable signal and partial portal coverage — documentation a human can read, but little a machine or agent can consume without scraping.

Kin Score

API Evangelist profiles Zeller the way a machine reads it — 6 machine-readable artifacts across 3 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.

Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Zeller scores 31.8/100 (thin), with a separate agent-readiness read of 15/100 (agent aware). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.

Kin Score

This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance. Every facet and dimension name is a link: it opens that measurement's page on APIs.io, where the rating runs across the whole catalog — the exact checks that feed it, how every profiled provider distributes on it, and who is at the top of it.

Kin Score Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0
Zeller Kin Score — API readiness rating by API Evangelist

Put this on your own site. The badge is drawn live from Zeller's current Kin Score — paste it once and it updates itself every time the score is recomputed. It follows your visitor's light or dark setting, and it links back here so anyone who sees it can read the full breakdown.

<!-- Kin Score · API Evangelist -->
<a href="https://providers.apievangelist.com/providers/zeller/"
   title="Zeller on API Evangelist — API profile and Kin Score">
  <img src="https://apis.io/badge/zeller.svg"
       alt="Zeller Kin Score — API readiness rating by API Evangelist" width="150" height="150" loading="lazy">
</a>

More shapes, themes and sizes → · Score as JSON · How badges work

How we profile Zeller

Each block below is one kind of artifact we hold for Zeller. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.

APIs 3

Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.

Individual APIs this provider publishes, each with its own machine-readable definition.

Zeller Terminal API

Connect point-of-sale software directly to Zeller Terminal hardware to initiate and manage in-person card payments. Delivered through the Zeller Payments SDK (React, React Nativ...

Zeller Online Payments API

Accept payments inside web and mobile apps via Zeller's Online integration. Part of the Zeller Developer Suite; access to full API documentation is by request behind a free deve...

Zeller Tap to Pay API

Accept contactless card and mobile-wallet payments on a phone with no separate terminal, integrated through the Zeller Payments SDK. Documentation is gated behind a free Zeller ...

MCP Servers 1

Model Context Protocol servers expose these APIs directly to AI agents. We profile them because agent-native access is the fastest-growing way this provider's capabilities actually get used.

Model Context Protocol servers that expose these APIs to AI agents.

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Zeller Authentication

oauth2/openIdConnect · 1 scheme

SECURITY

Zeller Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Resources

Every other property we hold for Zeller — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.

Get Started 2

Portal, sign-up, and the first successful call

Documentation 1

Reference material describing how the API behaves

Agent Surfaces 3

MCP servers, agent skills, and machine-readable catalogs

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

Build 3

SDKs, sample code, and the tooling you integrate with

Access & Security 3

Authentication, authorization, and security posture

Operate 1

Status, limits, changes, and where to get help

Commercial 3

Pricing, plans, and the legal terms of use

Company 3

The organization behind the API

← All providers · Data indexed from github.com/api-evangelist/zeller · machine-readable index on apis.io

Where this information came from

This is an independent, third-party profile of Zeller, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.

The Kin Score and Agent Readiness rating are independently calculated assessments of a company's public API artifacts, scored against a published rubric. They are not certifications, endorsements, security assessments, or audits.

Corrections, re-scores, and removal are free — no partnership or purchase required, and you do not need to justify the request. A removed company is recorded as unrated, never scored zero for having asked. Acknowledgement within one business day; removal within two.

info@apievangelist.com · Read the full data-sourcing policy →
On a security or compliance team? Put security in the subject line and you will get a person, not a form — we will tell you exactly which public URLs this profile was built from.