API Versioning
Definition updated April 2026
What is API versioning?
API versioning is the practice of managing changes to an API without breaking existing integrations. When an API evolves - adding endpoints, changing response formats, or removing deprecated fields - versioning lets old and new clients coexist.
The most common strategy embeds the version in the URL path, such as /v1/product-search and /v2/product-search. Header-based and query parameter versioning also exist but are less common.
When an API you depend on releases a new version, read the changelog before upgrading. Breaking changes - renamed fields, changed data types - require updates to your parsing code. Most APIs maintain previous versions for a deprecation period.
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