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Getting started
Learn how to authenticate, how data is stored, and how to make your first API calls.
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Guides
Developer guides
Read detailed guides for common developer use cases. Learn how our New APIs compare to our legacy APIs.
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Docs
API docs
Klaviyo's new and improved APIs are now available! Learn about our API objects, methods, attributes, and responses
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Developer tools
Speed up development with tools designed for your workflow.
SDKs
Install a Klaviyo maintained SDK to accelerate development– offered in Python, PHP, Ruby, and Node.
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Test accounts
Test custom integrations and apps without the risk of impacting your production account.
Create test account
Postman
Make test calls using Postman’s UI tool with our collection of pre-built API requests.
Test with Postman
Sample code repository
Find pre-built solutions, examples, and reference code guides in our Klaviyo Labs GitHub.
View code samples
Sample data
Populate your test account with sample data to quickly explore our API and see how data is used in Klaviyo.
Generate sample data
Napkin
Create and deploy serverless cloud functions instantly from the browser. Quickly add authentication for your API, schedule tasks, and replay events.
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Use cases
Build custom integrations to bring data into Klaviyo to create personalized experiences. Integrate with point-of-sale software, inventory management systems, scheduling apps, and more.
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Brian Whalley - Co-Founder of Wonderment
“Since Klaviyo doesn't impose a rigid data schema, it's easy to send in just about any arbitrary data without having to do annoying manipulations or data mappings and without having to pre-configure a data schema in the app.”
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Use profile information, custom events, catalog information, and other types of data to build custom customer experiences using Klaviyo's flows, template email builder, and more.
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Callum McMaugh - Techincal Lead at Giftnotes
“Merchants can set up flows based on Klaviyo events to send out branded notifications to both the [gift] recipient and the customer. They can also segment the customer and the recipient for greater insights into their customer’s shopping habits.”
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Pull data from Klaviyo to create dashboards, sync to other systems, and perform analysis to keep up with your marketing performance.
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Kyle Tremblay - Sr. Product Manger at EXCLUSIVE
“Integrating with Klaviyo’s APIs was a no-brainer as it allowed us to build reporting that’s informed by our clients’ goals. Additionally, we’re now able to highlight useful, holistic insights to determine what actions should be taken by our clients to meet their goals.”
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