White Label API Development Partners

White label API development delivered under your agency's name, covering REST and GraphQL services for internal tools and public-facing platforms. Each API is secure, scalable and built by our developers, then handed over for you to present as your own.

On-time Delivery

We stick to schedules and keep you informed every step of the way. Your clients see a reliable team with consistent delivery.

Invisible Partnership

We operate behind the scenes so your brand stays front and centre. All communication and output reflect your agency, not ours.

Built for Agencies

Our team has spent years delivering white label solutions for creative, digital, and technical agencies across many industries.

API-First Thinking

Whether REST or GraphQL, internal or public-facing, we design APIs that power modern platforms with clean, consistent structures.

Tight QA Standards

Every API is tested for performance, security, and reliability across expected use cases before it leaves our hands.

Developer-Led

Projects are led by technical managers who understand real-world engineering needs. You’ll never need to explain the same thing twice.

Some of our direct clients

QualityHive
Clintons Cards
Marmot Tours
Clive Christian
Pulse
Nucleus Commercial Finance
Squash Skills
Slick Gorilla
Coleg Gwent

APIs Built Properly, Documented Fully

REST and GraphQL APIs delivered under your brand, with authentication, security, rate limiting, and full documentation included as standard. You take the credit.

7+
Years delivering APIs for agencies
4-12wk
Build timeline depending on scope
100%
Documented and tested on handover
2 days
Typical quote turnaround
Illustrating why agencies trust us

Why Agencies Trust Us

We create powerful, custom-built APIs that serve real business needs while you remain the point of contact. Every API is secure, scalable, and built with care.

  • REST and GraphQL APIs
  • Authentication and Security
  • External and Internal Integrations
  • Clear, Maintainable Documentation

How a White Label API Project Works With Us

Step 1
Free 30-min call

We learn what the API needs to do

We start with a short call to understand what the API is for, who will consume it, and the systems it has to work with. No jargon and no commitment, just a clear read on the right approach, whether that is REST, GraphQL or an integration layer, and roughly what it would take.

Step 2
Within a few days

We design the endpoints and quote

We map out the endpoints, the data model and how authentication should work, including the edge cases most briefs leave out. You get a fixed-price proposal with a clear scope and timeline, written under your branding so you can pass it straight to your client.

Step 3
Build phase

We build, secure and test it

We build the API in a staging environment and test it against real, awkward data, not just the happy path. Security, rate limiting and error handling are built in from the start, and we document each endpoint as we go so nothing is left to reverse-engineer later.

Step 4
Launch and beyond

We hand it over ready for your name

We deploy the API with monitoring in place and hand over full documentation your team or your client's developers can use straight away. Everything carries your branding, and we are on hand for versioning, changes or ongoing support whenever the project grows.

Ready to deliver an API under your brand?

Tell us what the API needs to do and who will consume it, and we will come back with a fixed quote and a realistic timeline, usually within 2 working days. NDA first, no obligation.

Get a Quote

Here's What Our Partners Say

Agencies, direct clients and long-term retainers. Rated 5* on Google.

Zestcode really have proven to be “website design & development specialists” whilst maintaining the very best customer service. Not easy to find a well-rounded company like Zest these days that tick all the boxes. 5*

Ben Ryman
Ben Ryman

Head of Marketing, Masterclip

After working with Zestcode for over 2 years I wouldn’t trust any other web developers. An agency that are committed to getting the project right and going above and beyond expectations.

Alex Robinson
Alex Robinson

Director, Novus Digital

Harry and his team have just finished producing our new website, his team have done an amazing job producing our website and their continuous communication throughout made the process a lot easier.

Jason Phillips
Jason Phillips

Director, JL Phillips

Zestcode Digital have just finished my website and I am beyond thrilled with it! I highly recommend their services not only are they professional and proficient but incredibly helpful.

Anna-Maria Thetford
Anna-Maria Thetford

Director, Select Art Gallery

It's an easy and enjoyable process working with Zestcode Digital, highly recommended.

Jake Hughes
Jake Hughes

Director, Whoisvisiting

Their team is highly responsive, especially in time-sensitive situations, and their ability to deliver reliable solutions quickly has been a huge asset. I wouldn’t hesitate to recommend them to anyone looking for dependable web development support.

Peter Bollons
Peter Bollons

Marketing Manager, Slick Gorilla

Having close communication with Harry throughout the whole project has been invaluable. He always makes sure to explain things thoroughly and helped me understand all the different aspects of the project that I needed to know.

Maxwell Adams
Maxwell Adams

Director, All Abroad

Frequently Asked Questions

White Label API Development for Agencies and Their Clients

When an agency brings an API project to us, the questions are usually practical: what should the API actually do, will it hold up under real traffic, and can it be delivered under your brand without your client ever seeing us. Here is how we build APIs that answer all three.

What white label API development means for your agency

White label API development means we build the API and you own the relationship. Every proposal, update and piece of documentation carries your branding, and your client only ever deals with your team. We are the engineering capacity behind the scenes, not a name on the invoice.

In practice this lets you take on work that needs proper backend engineering without hiring for it or turning it away. You win the project, set the client's expectations and stay the single point of contact, while we handle the design, build and testing to the standard you would expect from your own developers.

It sits naturally alongside our wider white label web development work, so an API can be one piece of a larger build or a standalone service, whichever the job calls for.

The kinds of APIs we build

Most projects fall into a few shapes. Public-facing REST or GraphQL APIs that let third parties or a client's own front end pull and push data. Internal APIs that connect services within a platform. And integration layers that sit between a bespoke system and the outside tools it needs to talk to.

We choose REST or GraphQL on the merits of the project, not habit. REST is often the right call for straightforward, well-scoped resources, while GraphQL earns its place when clients need to request exactly the data they want across a complex model. If a project is really about joining existing systems together, our API integrations work is usually the better starting point.

We also build the APIs that power larger products, so this pairs closely with portal and platform development and white label SaaS development when the API is the backbone of an application rather than a bolt-on.

How we stay invisible behind your brand

The whole point of a white label service is that your client never sees a third party. We work under your agency's name from the first document onwards, and we are happy to communicate through your project tools, use your templates, and keep our own branding entirely out of the deliverables.

On the technical side that means clean, self-explanatory code and documentation that reads as yours, so if your team or a future developer picks it up, nothing points back to us. If you ever want us on a client call in a supporting role we can do that too, but the default is that we stay out of sight.

You brief us once and get output you can pass on as your own, without having to filter or rewrite it first.

Not sure what your client's API actually needs to do?

Describe the platform, the data involved and who will be calling it. We will tell you honestly what the API should cover and roughly what it would take to build.

Ask Us

Security, authentication and rate limiting

An API is a door into a system, so how it is secured matters as much as what it does. We handle authentication properly, usually with API keys, OAuth or token-based access depending on who is consuming the endpoint, and we scope permissions so each caller can only reach what it genuinely needs.

We build in rate limiting and sensible throttling from the start, so a single client or a misbehaving script cannot degrade the service for everyone else. Input is validated, errors return useful but not leaky responses, and anything sensitive is encrypted in transit.

Where an API handles personal or payment data we design with the relevant obligations in mind rather than adding them later, and we keep enough logging that you can see what was called, by whom and when.

Documentation, versioning and handover

A well-built API is only as useful as the documentation that comes with it. Every project ships with clear reference material covering endpoints, parameters, authentication and example requests, written so a developer consuming the API can get going without a call.

We version APIs sensibly so that future changes do not break the integrations already relying on them. When an endpoint needs to change, existing consumers keep working while the new version rolls out, which matters a great deal once real clients are depending on it.

Handover is deliberate, not a code dump. You get the documentation, a clear explanation of what was built and how, and a codebase your own team can maintain if they ever need to.

Performance, scaling and what it costs

APIs tend to start small and then get busy, so we build with that in mind. Efficient queries, caching where it helps, and pagination on anything that returns a list, so response times stay steady as usage grows rather than degrading the day the API becomes popular.

Cost depends on the shape of the work. A focused API over a defined data set is a smaller job than a full platform backend with complex business logic, so rather than a fixed rate card we scope each project and quote it properly. Where the API is powered by a Laravel backend, our white label Laravel development work often runs alongside it.

You get a fixed-price proposal with a clear scope before anything starts, so the number you quote your client is one you can stand behind.

Partner with Zestcode for Industry Leading Quality and Reliability

Tell what you're looking for and we'll see you how we can help. Quotes are typically provided within 2 working days of the initial call.

Get a Quote
Rated 5 stars on Google
Northamptonshire Based
Full Stack Development Team
White Label Specialists