generated: '2026-06-20'
method: searched
source: https://www.backblaze.com/docs/cloud-storage-native-api-versions
description: >-
  Backblaze versions the B2 Native API by whole numbers carried in the URL path
  (/b2api/v4/). A new version is cut for backwards-incompatible changes; older
  path versions keep working. This captures the dated version history; the live
  versions page is the source of truth.
docs: https://www.backblaze.com/docs/cloud-storage-native-api-versions
versioning:
  scheme: uri-path integer versions
  current: v4
  detail: lifecycle/backblaze-lifecycle.yml
entries:
  - version: v4
    date: '2025-04-29'
    latest: true
    breaking:
      - b2_authorize_account response drops bucketId/bucketName/infoType in favor of an `allowed` object (buckets, capabilities, namePrefix).
      - b2_create_key request/response replace bucketId with bucketIds; b2_delete_key and b2_list_keys responses use bucketIds.
    additions:
      - Multi-Bucket Application Keys — a key can grant access to a specific group of buckets, optionally limited to a single file prefix.
  - version: v3
    date: '2021-09-23'
    additions:
      - b2_authorize_account extended to work with multiple API suites (B2 Storage and Partner APIs); response reorganized by suite.
  - version: v2
    date: '2021-05-11'
    additions:
      - Object Lock (retention, legal hold) and Server-Side Encryption support.
      - List operations return serverSideEncryption, fileRetention, and legalHold; standardized file structure across operations.
  - version: v1
    date: '2018-07-26'
    additions:
      - Application key management and authorization controls (original B2 API launched 2015-09-22).