The post outlines Klaviyo’s expanded REST APIs and developer tools designed to support more flexible, data-driven ecommerce experiences. It explains new and revamped endpoints, efficiency-focused API features, and tooling that simplify integration, querying, and experimentation.
Expanded API surface: New catalogs, flows, and client-side APIs, plus revamped Events, Lists, Segments, Profiles, Templates, and Metrics endpoints, provide broader programmatic access aligned to a JSON:API standard.
More efficient data access: Compound documents, resource relationships, sparse fieldsets, and enhanced filtering and sorting reduce redundant queries and let developers request only the data they need.
Developer productivity tools: SDKs for Python, Node, Ruby, and PHP, along with a sample data tool for sandbox accounts, help teams build, test, and maintain integrations faster.
Ecommerce use cases: Examples include keeping product catalogs current for accurate personalization, auditing and benchmarking flow performance, and retrieving detailed profile membership data for targeted communication.
At Klaviyo, we empower creators to own their destinies. Since our founding in 2012, we have built infrastructure designed to process, store, analyze & act on vast amounts of customer data. Today, we’re focused on giving developers all the flexibility you need to power a new generation of data-driven experiences and applications.
With over 135,000 customers, our team believes that expanding Klaviyo as an API-first platform is the best way to empower developers to tackle brands’ own unique challenges and priorities. To do this, we are working to transform and expand your access to Klaviyo and your ability to integrate it with the rest of your tech stack, while making sure your experience as a Klaviyo developer is easy, intuitive, and enjoyable.
“We’ve just reached 100 customers using our Klaviyo → NetSuite integration. It has been incredible for our company’s growth. With our team’s expert knowledge of NetSuite and eCommerce websites, we’ve built the most robust integration for NetSuite using Klaviyo’s platform. We are looking forward to the next iteration of Klaviyo’s APIs, which will open up new use cases for our customers. It has been a massively fruitful partnership, and we are excited for Klaviyo’s next endeavor as an API-first company.”
Rodrigo Alonso, CEO of Tavano
We’ve talked with many of you about what you want out of Klaviyo, and we’ve made great strides this year to make your experience better: we’ve expanded our API surface area, we’ve launched new developer tools, and we’ve got more advances in the pipeline.
Here’s a look at what we’ve done in just this past quarter.
What’s new?
We’re releasing new endpoints to enable programmatic access to new product areas. We’re also rewriting all of our existing APIs and creating new API-driven functionality, so you can build more powerful experiences with Klaviyo. We’re focused on helping you scale and customize your ecommerce operations by expanding developer access to our product, giving you more functionality, and making data processing in Klaviyo more flexible and more efficient.
Now, you can:
Tailor Klaviyo to your needs with an expanded and improved API surfaceWe’ve launched brand new APIs including catalogs, flows, and client-side endpoints. These new features will, for example, make it easy to manage catalogs for brands and to utilize up-to-date data to populate product feeds, campaigns, and flows. These improvements will also make it easier to measure the performance of email flows by simplifying the process of pulling data and programmatically turning flows on and off.In addition to the new endpoints, we’ve revamped old ones, including Events, Lists, Segments, Profiles, Templates, and Metrics APIs adhering to our new JSON:API standard.
We’ve launched brand new APIs including catalogs, flows, and client-side endpoints. These new features will, for example, make it easy to manage catalogs for brands and to utilize up-to-date data to populate product feeds, campaigns, and flows. These improvements will also make it easier to measure the performance of email flows by simplifying the process of pulling data and programmatically turning flows on and off.
In addition to the new endpoints, we’ve revamped old ones, including Events, Lists, Segments, Profiles, Templates, and Metrics APIs adhering to our new JSON:API standard.
Pull more relevant data with less work with these enhanced API featuresCut out redundancy with compound documents and resource relationships: Now, brands and partners can easily hydrate responses without having to perform a multitude of redundant queries. We’ve improved API efficiency and reduced the number of requests required by “including” other related resource objects in the response.Run more efficient queries with sparse fieldsets: Request only the data you need to minimize response sizes. We’ve added the ability to specify just the response fields you need, so you can process data faster with reduced latency.Get more control over your results with enhanced filtering and sorting: Query for specific data and control how that data is returned. We’ve built out robust filtering and sorting operations so you can pull the exact data you need to execute a request. For example, sort based on data type like timestamp or alphabetical, or filter based on comparing literals like VIP-specific profiles via {“VIP”: true}.
Cut out redundancy with compound documents and resource relationships: Now, brands and partners can easily hydrate responses without having to perform a multitude of redundant queries. We’ve improved API efficiency and reduced the number of requests required by “including” other related resource objects in the response.
Run more efficient queries with sparse fieldsets: Request only the data you need to minimize response sizes. We’ve added the ability to specify just the response fields you need, so you can process data faster with reduced latency.
Get more control over your results with enhanced filtering and sorting: Query for specific data and control how that data is returned. We’ve built out robust filtering and sorting operations so you can pull the exact data you need to execute a request. For example, sort based on data type like timestamp or alphabetical, or filter based on comparing literals like VIP-specific profiles via {“VIP”: true}.
Save time with new toolingNew SDKs: Now, you can start building on Klaviyo in your choice of four languages: Python, Node, Ruby, and PHP. You no longer need to burn time on writing and maintaining boilerplate code. Instead, you can edit Klaviyo templates, campaigns, lists and segments and more with your preferred software development kit.Sample Data Tool: Our new sample data tool allows you to auto-populate fake data into your sandbox account, so you can experiment and build faster.
New SDKs: Now, you can start building on Klaviyo in your choice of four languages: Python, Node, Ruby, and PHP. You no longer need to burn time on writing and maintaining boilerplate code. Instead, you can edit Klaviyo templates, campaigns, lists and segments and more with your preferred software development kit.
Sample Data Tool: Our new sample data tool allows you to auto-populate fake data into your sandbox account, so you can experiment and build faster.
What’s possible?
With the expanded launch of our new Klaviyo APIs, we’ve seen a wide array of use cases for brands and partners to create innovative new experiences and applications, such as:
Have an updated product catalog in Klaviyo to make downstream Klaviyo features more effective: With the new Catalogs API, you can now create, update, or delete catalog data in a brand’s account — so the personalized emails you send through Klaviyo will always have accurate product information.
Easily understand your Klaviyo Flows Performance: Using our new Flows API, you are able to easily audit a brand’s flows by getting what flows are running as well as evaluating how the flows are performing (determining what is most successful to use as a benchmark or future example).
Quickly understand profile-specific information for more targeted communications: As a brand, understanding “which lists and segments does an individual belong to?” is critical. Now with the revamped Profiles API, you can get profile List and Segment membership data as well as custom profile properties to send more targeted and meaningful communication.
And more!
Want to start building the next Klaviyo experience for our 135K+ customers?
To learn more about Klaviyo’s new APIs and developer tools, visit developers.klaviyo.com, or reach out to the Developer Experience Team at developers@klaviyo.com.
See how the Social Insights Analyst analyzes your Instagram UGC to surface top creators, themes, and post performance, then act on it across email and text.
Reuse your top-performing Instagram posts across email, SMS, flows, and forms in Klaviyo. Pull proven content into every owned channel without downloads.
# Power a new generation of data-driven experiences with our new REST APIs
At Klaviyo, we [empower creators ](https://www.klaviyo.com/owned-marketing)to own their destinies. Since our founding in 2012, we have built infrastructure designed to process, store, analyze & act on vast amounts of customer data. Today, we’re focused on giving developers all the flexibility you need to power a new generation of data-driven experiences and applications.
With over 135,000 customers, our team believes that expanding Klaviyo as an [API-first platform](https://developers.klaviyo.com/en) is the best way to empower developers to tackle brands’ own unique challenges and priorities. To do this, we are working to transform and expand your access to Klaviyo and your ability to [integrate ](https://www.klaviyo.com/features/integrations)it with the rest of your tech stack, while making sure your experience as a Klaviyo developer is easy, intuitive, and enjoyable.
> “We’ve just reached 100 customers using our Klaviyo → NetSuite integration. It has been incredible for our company’s growth. With our team’s expert knowledge of NetSuite and eCommerce websites, we’ve built the most robust integration for NetSuite using Klaviyo’s platform. We are looking forward to the next iteration of Klaviyo’s APIs, which will open up new use cases for our customers. It has been a massively fruitful partnership, and we are excited for Klaviyo’s next endeavor as an API-first company.”
Rodrigo Alonso, CEO of Tavano
We’ve talked with many of you about what you want out of Klaviyo, and we’ve made great strides this year to make your experience better: we’ve expanded our [API surface area](https://www.klaviyo.com/product/whats-new/js-object), we’ve launched new developer tools, and we’ve got more advances in the pipeline.
Here’s a look at what we’ve done in just this past quarter.
## **What’s new? **
We’re releasing new endpoints to enable programmatic access to new product areas. We’re also rewriting all of our existing APIs and creating new API-driven functionality, so you can build more powerful experiences with Klaviyo. We’re focused on helping you scale and customize your ecommerce operations by expanding developer access to our product, giving you more functionality, and making data processing in Klaviyo more flexible and more efficient.
Now, you can:
- **Tailor Klaviyo to your needs with an expanded and improved API surface**We’ve launched brand new APIs including catalogs, flows, and client-side endpoints. These new features will, for example, make it easy to manage catalogs for brands and to utilize up-to-date data to populate product feeds, campaigns, and flows. These improvements will also make it easier to measure the performance of [email flows](https://www.klaviyo.com/features/ecommerce-marketing-automation) by simplifying the process of pulling data and programmatically turning flows on and off.In addition to the new endpoints, we’ve revamped old ones, including Events, Lists, Segments, Profiles, Templates, and Metrics APIs adhering to our new JSON:API standard.
- We’ve launched brand new APIs including catalogs, flows, and client-side endpoints. These new features will, for example, make it easy to manage catalogs for brands and to utilize up-to-date data to populate product feeds, campaigns, and flows. These improvements will also make it easier to measure the performance of [email flows](https://www.klaviyo.com/features/ecommerce-marketing-automation) by simplifying the process of pulling data and programmatically turning flows on and off.
- In addition to the new endpoints, we’ve revamped old ones, including Events, Lists, Segments, Profiles, Templates, and Metrics APIs adhering to our new JSON:API standard.
- **Pull more relevant data with less work with these enhanced API featuresCut out redundancy with compound documents and resource relationships: **Now, brands and partners can easily hydrate responses without having to perform a multitude of redundant queries. We’ve improved API efficiency and reduced the number of requests required by “including” other related resource objects in the response.**Run more efficient queries with sparse fieldsets:** Request only the data you need to minimize response sizes. We’ve added the ability to specify just the response fields you need, so you can process data faster with reduced latency.**Get more control over your results with enhanced filtering and sorting: **Query for specific data and control how that data is returned. We’ve built out robust filtering and sorting operations so you can pull the exact data you need to execute a request. For example, sort based on data type like timestamp or alphabetical, or filter based on comparing literals like [VIP-specific profiles](https://www.klaviyo.com/features/segmentation) via {“VIP”: true}.
- **Cut out redundancy with compound documents and resource relationships: **Now, brands and partners can easily hydrate responses without having to perform a multitude of redundant queries. We’ve improved API efficiency and reduced the number of requests required by “including” other related resource objects in the response.
- **Run more efficient queries with sparse fieldsets:** Request only the data you need to minimize response sizes. We’ve added the ability to specify just the response fields you need, so you can process data faster with reduced latency.
- **Get more control over your results with enhanced filtering and sorting: **Query for specific data and control how that data is returned. We’ve built out robust filtering and sorting operations so you can pull the exact data you need to execute a request. For example, sort based on data type like timestamp or alphabetical, or filter based on comparing literals like [VIP-specific profiles](https://www.klaviyo.com/features/segmentation) via {“VIP”: true}.
- **Save time with new toolingNew SDKs:** Now, you can start building on Klaviyo in your choice of four languages: Python, Node, Ruby, and PHP. You no longer need to burn time on writing and maintaining boilerplate code. Instead, you can edit [Klaviyo templates](https://www.klaviyo.com/features/templates), campaigns, lists and segments and more with your preferred software development kit.**Sample Data Tool:** Our new sample data tool allows you to auto-populate fake data into your sandbox account, so you can experiment and build faster.
- **New SDKs:** Now, you can start building on Klaviyo in your choice of four languages: Python, Node, Ruby, and PHP. You no longer need to burn time on writing and maintaining boilerplate code. Instead, you can edit [Klaviyo templates](https://www.klaviyo.com/features/templates), campaigns, lists and segments and more with your preferred software development kit.
- **Sample Data Tool:** Our new sample data tool allows you to auto-populate fake data into your sandbox account, so you can experiment and build faster.
## **What’s possible?**
With the expanded launch of our new Klaviyo APIs, we’ve seen a wide array of use cases for brands and partners to create innovative new experiences and applications, such as:
- **Have an updated product catalog in Klaviyo to make downstream Klaviyo features more effective: **With the new Catalogs API, you can now create, update, or delete catalog data in a brand’s account — so the [personalized emails ](https://www.klaviyo.com/email-marketing)you send through Klaviyo will always have accurate product information.
- **Easily understand your Klaviyo Flows Performance: **Using our new Flows API, you are able to easily audit a brand’s flows by getting what flows are running as well as evaluating how the flows are performing (determining what is most successful to use as a benchmark or future example).
- **Quickly understand profile-specific information for more targeted communications: **As a brand, understanding “which lists and segments does an individual belong to?” is critical. Now with the revamped Profiles API, you can get profile List and Segment membership data as well as custom profile properties to send more targeted and meaningful communication.
- **And more!**
### **Want to start building the next Klaviyo experience for our 135K+ customers?**
To learn more about Klaviyo’s new APIs and developer tools, visit [developers.klaviyo.com](https://developers.klaviyo.com/en), or reach out to the Developer Experience Team at developers@klaviyo.com.
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