Quick answer
Backblaze B2 Cloud Storage - Backblaze B2 Cloud Storage wins for most builders who want an actually persistent free tier, while Amazon S3 is better if you want a short-lived AWS credit that can cover broader AWS usage.
How the free tiers compare
These products solve the same storage problem in very different ways. Amazon S3 gives you a temporary AWS Free Tier credit bucket, so the value is broad but time-limited: you get up to $200 in eligible AWS credits for 6 months, and S3 sits inside a much larger AWS account you can later expand into. Backblaze B2 is narrower but more predictable: 10GB stays free, with permanent rules around storage, egress, and API calls. That makes B2 easier to keep around for a small project, backup, or side app without a clock running. S3 becomes more attractive if you already expect to grow into AWS services or need one account for many workloads. B2 is the cleaner fit if the question is simply “what storage can I keep using for free or near-free?”
Amazon S3 vs Backblaze B2 Cloud Storage free tier, side by side
| Amazon S3FTV 57 | Backblaze B2 Cloud StorageFTV 35 | |
|---|---|---|
| Free offer typeS3 credits apply to eligible AWS services and expire over time; B2 free storage is perpetual. | Up to $200 in AWS Free Tier credits | First 10GB of storage always free |
| Free tier durationB2’s free storage is ongoing; other usage can still be billed. | 6 months after account creation | No fixed end date stated |
| Free storageS3’s free value comes as credits, not a storage cap. | Not specified as a standalone storage allowance | 10GB |
| EgressB2 ties free egress to storage volume. | First 100 GB/month free internet egress | Free up to 3x average monthly storage; $0.01/GB beyond that |
| API callsB2 includes explicit free API call allowances. | Not specified | Class A free; Class B and C free for first 2,500/day per class |
| Credit validityS3’s free value is time-limited even if not fully used. | Credits must be used within 12 months of account creation | Not applicable |
After you outgrow the free tier
Both products use usage-based pricing after the free tier, but they diverge in how predictable that usage is. Amazon S3 has no minimum charge and bills separately for storage class, requests, retrieval, transfer, replication, and analytics features. Backblaze B2 starts at $6.95 per TB per month for storage, with egress free up to 3x average monthly storage and overage at $0.01/GB. B2 Reserve and Overdrive add more specialized pricing, but without public exact rates for Reserve. For a small builder, B2 is usually easier to forecast; S3 can be cheaper or more expensive depending on which S3 features you touch.
Cost at real usage
| Usage | Amazon S3 | Backblaze B2 Cloud Storage |
|---|---|---|
| 10GB storage / monthS3 does not publish a simple storage-only monthly floor here. | ~$0 with AWS credits if within free tier window; otherwise usage-based | Free (within always-free 10GB) |
| 100GB internet egress / monthB2’s egress free allowance depends on stored data, so exact cost cannot be fixed from the input. | Free for the first 100 GB/month | Free up to 3x average monthly storage; cost varies if you exceed that rule |
| 1TB storage / monthB2 storage is priced directly; S3 pricing varies by storage class and other factors. | Usage-based, exact cost not provided | $6.95/mo |
| 10TB storage / monthThis ignores B2 egress and API call charges, which may be free or extra depending on usage. | Usage-based, exact cost not provided | $69.50/mo |
Estimates, not quotes. Usage-based rates change - verify with the vendor's pricing page before committing.
When to pick each one
Pick Amazon S3 when…
- You want to test S3 as part of a broader AWS stack, not just object storage.
- You can use AWS Free Tier credits across multiple eligible AWS services, not only storage.
- You expect a short prototype or migration spike and can finish within the 6 month free plan window.
- You already plan to move onto AWS usage-based billing and want the credits to soften the start.
Pick Backblaze B2 Cloud Storage when…
- You want a storage tier that does not depend on a one-time credit clock.
- You need a small always-free bucket for backups, static assets, or app files.
- You care about predictable storage and egress rules as usage grows.
- You want S3 compatibility but do not want AWS account sprawl or broader AWS service billing.
Bottom line
For most builders choosing a free tier, Backblaze B2 Cloud Storage is the better default because the free storage is permanent and the pricing stays easier to reason about once you grow. Amazon S3 only wins when you specifically want AWS credits and expect to live inside the AWS ecosystem, where the free tier can subsidize more than storage. If you just need a small bucket for a project, backup, or app asset store, B2 is the cleaner long-term choice.
Read the full listings: Amazon S3 and Backblaze B2 Cloud Storage. Scores use the FTV methodology at /ftv. Browse more head-to-heads on /compare, or see the top-ranked free tiers on /top.