Cloud Parts

Backblaze B2 Cloud Storage

Low-cost object storage on Backblaze’s own hardware, with its own API and an S3-compatible one.

What it is
Object storage
Type
Commercial product
Made by
Backblaze, Inc.
License
Proprietary (the b2 CLI is open source)
Facts checked
5 October 2026
Website

What it is

B2 keeps files on hardware Backblaze designs and runs itself. Storage Pods, servers packed with hard drives, are grouped into Vaults of 20, and each file is split into 17 data shards and 3 parity shards spread across the 20 pods, so a Vault can lose three whole pods without losing data. There are two ways in. The B2 Native API starts with b2_authorize_account, which returns a token; to upload, the client calls b2_get_upload_url and sends the bytes straight to the Vault that URL points at, so there is no central load balancer in the way. Since 2020 the same buckets also answer an S3-compatible API at https://s3.<region>.backblazeb2.com, which covers common tools but leaves out object ACLs, IAM roles, object tagging, website configuration and browser POST uploads. An account’s data lives in one of four regions (US West, US East, EU Central in Amsterdam, CA East in Toronto), picked at sign-up and fixed after that.

Pricing is storage-led. Since 1 May 2026 B2 costs $6.95 per TB-month (it was $6), the first 10 GB is free, and there are no minimum storage duration or minimum file size fees. Standard API calls are free for pay-as-you-go customers. Downloads are free up to three times your average stored data each month and $0.01 per GB beyond that, except through partner CDNs and clouds such as Cloudflare, Fastly, bunny.net and Vultr, where they stay free. B2 Overdrive, aimed at AI and high-performance computing, starts at $15 per TB-month with unlimited free egress. Backblaze, which also sells computer backup, is listed on NASDAQ as BLZE.

Why teams pick it

  • The lowest list price per TB in the comparison below, with no minimum duration or minimum object size, so short-lived data isn’t penalised
  • Downloads free up to three times your stored data, and unlimited through partners such as Cloudflare and Fastly
  • Standard API calls cost nothing, so millions of small requests don’t add up
  • A long public record: open Storage Pod designs since 2009 and drive failure statistics from its fleet since 2014

Watch out for

  • The region is fixed per account at sign-up; moving means a new account and re-uploading, or paying for Cloud Replication while data sits in two places
  • The S3 API is partial: no object-level ACLs, IAM roles, object tagging, static website configuration or browser POST uploads
  • Egress beyond three times the stored data costs $0.01 per GB unless it goes through a partner, so a download-heavy public bucket can still pay for bandwidth
  • Only four regions, and prices have risen: $5 per TB at launch, $6 until April 2026, $6.95 since

Alternatives

What all object storage have in common →
Amazon S3AWSAWS’s object storage, and the de facto API most object stores copy.Apache OpenDALOpen sourceA Rust library, with bindings for Python, Java, Node.js, Go and more, that gives one API (read, write, stat, list, delete) over 50-plus storage backends: S3 and other object stores, local and HDFS file systems, Google Drive and Dropbox, and key-value stores.Apache OzoneOpen sourceA Hadoop-born object store that serves the same buckets over S3 and as a Hadoop file system.Azure Blob StorageAzureAzure’s object storage, with three blob types and an optional real directory tree for analytics.CephOpen sourceA distributed storage cluster that serves S3 buckets, block devices and a file system from the same pool of disks.Cloudflare R2CommercialS3-compatible object storage from Cloudflare that charges nothing for data going out.GarageOpen sourceA lightweight S3 object store that keeps copies of your data in several sites linked by ordinary Internet connections.Google Cloud StorageGoogle CloudGoogle Cloud’s object storage, where even the archive class answers in milliseconds.MinIOArchivedOpen sourceA self-hosted object store that speaks the S3 API. The open-source edition is archived and its images are gone from Docker Hub; MinIO now sells AIStor.PGSTY SiloOpen sourceA community-maintained fork of the open-source MinIO server, with builds, images, security fixes and the full web console.RustFSOpen sourceA young Rust reimplementation of MinIO’s design: S3-compatible, erasure-coded, Apache 2.0, and generally available since September 2026.SeaweedFSOpen sourceA distributed blob store with an S3 gateway and a file system layer, built to store and serve billions of small files.TigrisCommercialGlobally distributed S3-compatible object storage that moves data to where it’s read, with no egress fees.Versity S3 GatewayOpen sourceA stateless S3 server that exposes an existing file system, or another object store, through the S3 API.Wasabi Hot Cloud StorageCommercialS3-compatible object storage sold at one flat price per TB, with no egress or request fees.Zenko CloudServerOpen sourceScality’s open-source Node.js S3 server: a light S3 endpoint for development and tests, and a front end that can store objects in other clouds.

How it fits with other technologies

Create a bucket with the b2 CLI, then use it through the S3 API · bash

pip install b2
export B2_APPLICATION_KEY_ID="..." B2_APPLICATION_KEY="..."

b2 bucket create acme-backups allPrivate
b2 file upload acme-backups pg-2026-10-05.dump.gz postgres/pg-2026-10-05.dump.gz
b2 ls b2://acme-backups/postgres/

# the same bucket through the S3-compatible API; the endpoint is shown on the bucket page
export B2="https://s3.us-west-004.backblazeb2.com"
aws s3 ls s3://acme-backups/postgres/ --endpoint-url "$B2"
aws s3 presign s3://acme-backups/postgres/pg-2026-10-05.dump.gz --endpoint-url "$B2" --expires-in 3600

Next to S3 and R2#

Wasabi, Backblaze B2 and Tigris all speak the S3 API, but they sell different things: Wasabi and B2 a low flat price per TB, Tigris data placed near whoever reads it. List prices, checked on 5 October 2026.

WasabiBackblaze B2TigrisAmazon S3 StandardCloudflare R2 Standard
Storage, per GB-month$0.0078 ($7.99 per TB)$0.00695 ($6.95 per TB)$0.02$0.023 (first 50 TB)$0.015
Egress to the internetFree while monthly egress stays at or below the data storedFree up to 3× the average data stored, then $0.01 per GB; free through partner CDNsFree$0.09 per GB for the first 10 TB, after 100 GB freeFree
Request feesNoneFree, except Class D calls: $0.004 per 10,000 after 2,500 a day$0.005 per 1,000 writes, $0.0005 per 1,000 reads$0.005 per 1,000 writes, $0.0004 per 1,000 reads$4.50 per million writes, $0.36 per million reads
Minimum storage duration90 days (pay as you go)NoneNone (30 days Infrequent Access, 90 days Archive)None (30 to 180 days in colder classes)None (30 days Infrequent Access)
Other minimums, free allowance1 TB billed every month; objects billed as at least 4 KBFirst 10 GB free5 GB, 10,000 writes and 100,000 reads free each monthNo minimum charge; Free Tier credits for new accounts10 GB-month, 1 million writes and 10 million reads free each month
Regions16; each bucket lives in the region you pick4; chosen per account at sign-up and fixed8 behind one endpoint; Global buckets follow their readersEach bucket lives in the AWS Region you pickOne endpoint per account, region auto
  • Wasabi’s price is for North America and EMEA; the S3 prices are for US East (N. Virginia).
  • A minimum storage duration means an object deleted or overwritten sooner is still billed for the full period. On Wasabi it applies to all pay-as-you-go storage, not just a cold tier.

Getting data out without paying for it#

B2’s egress rules reward steady storage and punish bursts of downloads. These are the ways the pricing page lists to stay at zero.

Stay under 3×

every customer

Each month you can download up to three times your average stored data free. A 10 TB bucket can serve 30 TB a month before the $0.01 per GB rate starts.

Serve through a partner CDN

Cloudflare, Fastly, bunny.net, CacheFly

Egress to these CDNs is free beyond the 3× allowance. With Cloudflare in front of a public bucket, Backblaze charges no download fees and Cloudflare caches the files.

Compute at a partner cloud

CoreWeave, Equinix Metal, Vultr, phoenixNAP

Reading data into machines at these providers is free too, so the bucket can sit at Backblaze while the compute runs elsewhere.

B2 Overdrive

from $15 per TB-month

A higher-priced tier for AI and high-performance computing that includes unlimited free egress.

See it in a real stack

No architecture uses Backblaze B2 Cloud Storage yet. Drop it into the playground and wire it up yourself.Open playground →
Where it came from2007–2021

Backblaze was founded in 2007 to sell unlimited computer backup for $5 a month. That only worked if raw storage was cheap, and off-the-shelf systems, from Amazon S3 to SAN arrays, cost “10 times as much (or more) than the raw hard drives”. So in September 2009 the company published the design of its own Storage Pod, a 4U server with 45 drives holding 67 TB for about $7,867 in parts, running Debian and the JFS file system, and invited others to copy and improve it. In January 2014 it began publishing failure rates for the tens of thousands of drives in its fleet, the start of its Drive Stats reports.

In 2015 Backblaze grouped pods into Vaults, 20 pods that each hold one shard of every file, and on 22 September Gleb Budman announced B2: the same storage, sold directly, at $0.005 per GB-month and $0.05 per GB downloaded, with uploads free. “Our storage systems were large enough, the tech advanced enough, and the team large enough to pull this off,” he wrote.

B2 launched with its own API. In May 2020 Backblaze added an S3-compatible one, Budman’s “most requested feature”, so S3 tools could switch by changing an endpoint. The company went public on NASDAQ in November 2021 with about 2 exabytes under management.

Why it’s built this way

Build its own storage servers
Commercial storage cost ten times the drives inside it, which an unlimited $5 backup plan couldn’t carry. Years of publishing its designs and operational data also brought requests to use that storage directly, which became B2.
Erasure coding across 20 pods
Splitting each file into 17 data and 3 parity shards on separate pods survives three pod failures at once with about 18% extra storage, where three full copies would need 200%.
Clients upload straight to a Vault
The native API hands each client a URL for a specific Vault, so traffic doesn’t funnel through a central gateway and capacity grows by adding Vaults.
A native API first, S3 later
B2 launched in 2015 with its own simpler API. Customers kept asking for S3 so their existing software would work, and it arrived in 2020.

Timeline

  1. 2007

    Backblaze is incorporated in April to sell unlimited computer backup

  2. 2009

    Publishes the Storage Pod design: 45 drives, 67 TB, about $7,867

  3. 2014

    Starts publishing hard drive failure rates from its fleet

  4. 2015

    Vault architecture; B2 announced on 22 September at $0.005 per GB

  5. 2020

    S3-compatible API added on 4 May

  6. 2021

    IPO on NASDAQ as BLZE at $16 a share

Sources23 · facts checked 5 October 2026

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