OPENSRS API
Whether you're building your first product or scaling an existing one, the OpenSRS APIs integrate seamlessly with what you’ve built.
Trusted by some of the world's largest platforms.
Your customers are building businesses, stores, agents, and tools inside your product, and every domain they register elsewhere pulls them out of the experience you've built.
With the OpenSRS APIs, sell and manage domains, TLS/SSL certificates, and professional email under your brand, so your product is the only one they need.
Without OpenSRS
Customer leaves your platform to register a domain, purchase TLS/SSL certificates, and email
Third-party checkout, third-party brand
Someone else owns the launch moment
Support gets fragmented
With OpenSRS
Customer does it all inside your product
Your checkout, your brand
You own the relationship
Your product stays at the center of the experience
Two dedicated APIs. One partner.
OpenSRS offers two APIs—one for domain registration and TLS/SSL certificates, one for email hosting. Use them together or separately. Either way, your customers only ever see you.
Domains + TLS/SSL API
The full domain and TLS/SSL certificate experience, built into your product and branded as yours.
Best for AI app builders, website builders, e-commerce platforms, SaaS tools, hosting platforms, and marketplaces that want to own the domain experience.
Domain search and registration inside your product
TLS/SSL certificate purchases and provisioning
750+ TLDs, including premium domains
Full automation: registrations, renewals, transfers, and WHOIS updates
XML-based API that works with whatever stack you're building on
Email API
White-label professional email that lives inside your product, not someone else’s.
Best for platforms that want to help customers look legit from day one with addresses like hello@theirbrand.com.
Mailbox creation and management
Branded business email for customers’ domains
Bulk create, manage, and delete actions
IMAP, POP3, and SMTP support
JSON-based API that works with any stack
Why OpenSRS? A partner built for builders.
Infrastructure that’s been running since before “the cloud” was a thing. 25+ years. Millions of domains. Millions of mailboxes.
We're the infrastructure. Not the competition.
We never compete for your customers. They search for a domain inside your product. We're the infrastructure powering it.
No minimums, no ceilings.
Sign up, integrate, and scale at your own pace.
Transparent pricing.
Wholesale prices for all TLDs are on our site. No surprises. Tiered pricing grows with your volume.
Support that meets you where you are.
Documentation, code examples, and a team that helps builders go from integration to launch.
TESTIMONIAL
ikas is an e-commerce platform helping small businesses build and scale online stores.
Your users are ready to launch. Don’t send them somewhere else.
Add domains, hosted email, and TLS/SSL to your product with OpenSRS APIs. Speak with our sales team to get started.
Frequently Asked Questions
Do I need to be a developer to integrate the API?
Is there a testing environment?
Are there usage limits?
Are the two APIs different technically?
How does pricing work?
The API doesn't feel like the right fit — what else should I consider?
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