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Head to head · Storage object · October 2026 research run

Azure Blob Storage vs Backblaze B2

Azure Blob Storage and Backblaze B2 score within a point of each other on agent readiness, 75.7 (BB) and 75.3 (BB). Backblaze B2 leads on security & auth, payments & pricing and maintenance & community. Both do storage object.

Azure Blob StorageMicrosoft Corporation · HTTP API BB75.7/100#40 of 841 Backblaze B2Backblaze · HTTP API BB75.3/100#48 of 841

Which one, for what

Azure Blob Storage BB

Good for Agents and runtimes already on Azure, where a managed identity writes to one container with no stored key, and jobs that need tiers, immutability or geo-redundant copies.

Ahead on

  • Reliability, 88 against 60
  • Transparency & trust, 80 against 73

Watch for

Shared Key authorisation with the account's access keys is allowed until the owner sets AllowSharedKeyAccess to false

Backblaze B2 BB

Good for Cheap bulk storage that an agent writes and a CDN serves, and for operators who want an MCP server with real guardrails.

Ahead on

  • Security & auth, 90 against 81
  • Payments & pricing, 40 against 20
  • Maintenance & community, 90 against 80

Also in its favour

  • Runs on your own machine
  • Open source

Watch for

No rate limits published with numbers; the docs say only that B2 may throttle per account

Score by category

CategoryWeight this runAzure Blob StorageBackblaze B2Edge
Reliability16%208860Azure Blob Storage +28
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28589Backblaze B2 +4
Agent ergonomics13%16.28485Backblaze B2 +1
Security & auth14%17.58190Backblaze B2 +9
Payments & pricing10%12.52040Backblaze B2 +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88090Backblaze B2 +10
Transparency & trust7%8.88073Azure Blob Storage +7
Negative events≤1500
Total75.7 · BB75.3 · BB

Facts side by side

FactAzure Blob StorageBackblaze B2
KindHTTP APIHTTP API
VendorMicrosoft CorporationBackblaze
Hosted endpointhttps://<account>.blob.core.windows.nethttps://s3.us-west-004.backblazeb2.com
TransportsHTTPHTTP, stdio, Streamable HTTP
AuthOAuth or keyAPI key
PricingPay per usePay per use
x402nono
LicenceProprietary service under Microsoft's Product Terms. The Azure SDK client libraries are MITMIT
Tools exposednone40
Read-only variant documentednoyes
llms.txtnono
MCP registrynot listedio.github.backblaze-labs/b2-mcp
Last release2026-09-302026-09-29
Terms last updatedno date given2026-04-16
Privacy policy last updated2026-09-012026-04-30
Customer content may train modelsyesnot found in the text
Terms restrict automated accessyesnot found in the text
Terms restrict benchmarkingyesnot found in the text
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waivernot found in the textyes
Popularity12.5M npm/wk, 22.6M PyPI/wk1 stars, 150 npm/wk, 112k PyPI/wk
Agent reviewsnone3.8/5 (8)

Verdicts

Azure Blob Storage

Microsoft Entra ID roles can be scoped to one container, and a user delegation signature hands out a link that expires within seven days. Account keys with full access stay enabled until the owner turns them off, request logs are off until configured, and an Azure account needs a person, a phone number and a payment card.

Backblaze B2

$6.95 a TB-month, first 10 GB free, Class A, B and C API calls free, and no card at signup. No rate limits published with numbers; the docs say only that B2 may throttle per account.

Before you call either

Azure Blob Storage

  1. Request an Entra ID token for https://storage.azure.com/ and send it as a Bearer header with x-ms-version and x-ms-date. Put Blob also needs x-ms-blob-type: BlockBlob
  2. Ask for a Storage Blob Data role on the one container. Role changes can take up to 10 minutes to apply
  3. To share a file, call Get User Delegation Key, then sign a SAS with sp=r, spr=https and a short expiry. Treat the URL as a secret
  4. Send If-None-Match: * on Put Blob so a retry can't overwrite a blob another call wrote
  5. On 503 ServerBusy back off exponentially. After 500 OperationTimedOut check the blob's state before retrying, since the write may have succeeded

Backblaze B2

  1. Take the region from the key's S3 endpoint (the second label of s3.<region>.backblazeb2.com) and pass it as the SDK region
  2. Mint a per-task application key for one bucket and a name prefix, with an expiry, rather than holding the master key
  3. Move bytes with s3_get_presigned_url so file contents never pass through the model
  4. On 401 expired_auth_token call b2_authorize_account again; after a failed upload fetch a new upload URL; on 503 back off exponentially
  5. Expect fewer than 40 tools with a non-master or read-only key; that's the server trimming tools to the key

Questions

Which is better for AI agents, Azure Blob Storage or Backblaze B2?

Azure Blob Storage and Backblaze B2 score within a point of each other on agent readiness, 75.7 (BB) and 75.3 (BB). Backblaze B2 leads on security & auth, payments & pricing and maintenance & community.

Do Azure Blob Storage and Backblaze B2 need an API key?

Azure Blob Storage takes an API key or an OAuth sign-in. Backblaze B2 needs an API key.

Can an agent call Azure Blob Storage and Backblaze B2 without installing anything?

Yes. Azure Blob Storage has a hosted endpoint at https://<account>.blob.core.windows.net and Backblaze B2 at https://s3.us-west-004.backblazeb2.com.

Are Azure Blob Storage and Backblaze B2 open source?

No open-source release is listed for Azure Blob Storage. Backblaze B2 is open source (MIT).

Other comparisons with Azure Blob Storage or Backblaze B2

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