Guide
S3-compatible is an API claim, not a pricing or feature promise
Prices checked · Vendor details further down checked
16 of 18 vendors speak the Amazon S3 API, so a backup tool that writes to S3 can usually write to them; among them a 10 TB backup costs least at OVHcloud Object Storage Infrequent Access, $44.65 a month. Google Cloud Storage documents only partial S3 support, so test your backup tool before relying on it. Azure Blob Storage uses its own API.
| Vendor | Speaks the S3 API | 10 TB normal month | 10 TB restore month |
|---|---|---|---|
| OVHcloud Object Storage Infrequent Access · France (Gravelines) | Yes | $44.65 | $85.25 |
 Telnyx Cloud Storage Regular Storage · United States (US East) | Yes | $55.83 | $55.83 |
| IDrive e2 IDrive e2 · United States (Virginia) | Yes | $60.00 | $60.00 |
| Tigris Archive Instant Retrieval · Automatic location | Yes | $68.59 | $348.49 |
 Backblaze B2 B2 Cloud Storage · United States (US West) | Yes | $69.43 | $69.43 |
| DigitalOcean Spaces Spaces Cold Storage · United States (New York 3) | Yes | $70.19 | $171.71 |
 Wasabi Hot Cloud Storage · United States (US East 1) | Yes | $72.67 | $72.67 |
 Storj Standard · Distributed worldwide | Yes | $77.00 | $147.00 |
| Hetzner Object Storage Object Storage · Germany (Falkenstein) | Yes | $88.80 | $100.69 |
 Scaleway Object Storage Standard One Zone · France (Paris) | Yes | $100.51 | $212.75 |
| Oracle OCI Object Storage Infrequent Access · United States (Ashburn) | Yes | $103.08 | $203.01 |
 Cloudflare R2 Infrequent Access · Automatic location | Yes | $120.80 | $221.70 |
| Filebase Object Storage · Distributed worldwide | Yes | $139.70 | $139.70 |
| Amazon S3 S3 Glacier Instant Retrieval · United States (Northern Virginia) | Yes | $170.01 | $1,297.60 |
| Vultr Object Storage Standard · United States (New Jersey) | Yes | $180.00 | $280.00 |
| Akamai Cloud Object Storage Object Storage · United States (US East) | Yes | $200.00 | $250.00 |
| Google Cloud Storage Coldline · United States (South Carolina) | Partly, in 8 of 9 offers | $185.04 | $1,498.89 |
| Azure Blob Storage Cold LRS · United States (East US) | No | $170.83 | $1,347.23 |
Each vendor's cheapest complete bill for 10 TB kept, 1 TB downloaded in a normal month and all 10 TB in the month you restore, in storage readable at once where we know the vendor's ready time. "Yes" means the vendor documents an S3-compatible API; which S3 features it supports still differs, so check your backup tool's list. "Partly" means the vendor says only some S3 tools work, so we do not count it as compatible.
Put your own numbers through the calculator to see what this charge does to a normal month and to the month you restore.
S3-compatible means compatible with an API surface, not identical to Amazon S3
S3-compatible storage implements some or all of the Amazon S3 API surface so software written for S3-style buckets and objects can communicate with the service. The exact operation list, authentication behavior, limits, and extensions can differ. [1] [2] [3]
A yes on compatibility does not prove support for multipart edge cases, versioning, lifecycle rules, Object Lock, legal holds, governance mode, compliance mode, or one backup tool's repository workflow. Those requirements must be checked separately. [1] [4] [5]
Show the tableas checked 26 July 2026
| Claim | What it establishes | What it does not establish | Source |
|---|---|---|---|
| S3-compatible endpoint | The service accepts documented S3-style API calls [1] | That every Amazon S3 operation is implemented | [1] |
| S3-aware backup tool | The tool can attempt its S3 workflow against the endpoint [2] | That every call, permission, or retention feature the tool uses succeeds | [2] |
| Object Lock support | A separate retention API, when the vendor documents it [5] | It cannot be inferred from generic S3 compatibility | [5] [1] |
| Price compatibility | does not apply. API naming does not standardize storage, request, retrieval, or egress prices [6] [7] | That two compatible providers produce the same bill | [6] [7] |
The checked offers include 49 compatible, 8 incompatible, and 9 Google offers we do not count as compatible
Across 66 checked offers, 49 are documented as S3 compatible and all 8 Azure Blob offers are not. Google documents partial support for Cloud Storage: its XML API works with some tools and libraries built for Amazon S3 once they point at Google's endpoint and use Cloud Storage HMAC keys. Google does not claim full S3 compatibility, and Rapid storage's zonal buckets do not support HMAC keys at all, so we count none of the 9 Google offers as compatible. A partial or missing answer is never treated as compatible. [9] [10] [8]
The table keeps each vendor's answer as published: an unpublished answer is not counted as yes, and no is not a quality judgment. It answers only whether the offer we checked documents S3 compatibility. [8]
Show the table (18 vendors)as checked 26 July to 25 October 2026
| Provider | Offers we checked | S3-compatible? | What it means | Source |
|---|---|---|---|---|
| Amazon S3 | 16 | 16 yes [8] [11] | Reference API; class and bucket-type feature scope still varies | [8] |
| Azure Blob Storage | 8 | 8 no [8] | The offer we checked is not marked S3-compatible | [8] |
| Google Cloud Storage | 9 | 8 partial, 1 not supported [9] [10] [12] | Standard, Nearline, Coldline and Archive: the XML API works with some S3 tools and libraries after changing the endpoint and using HMAC keys, but full S3 compatibility is not claimed, so test your backup tool first. Rapid: zonal buckets do not support HMAC keys [9] [10] | [8] [9] [10] [12] |
| Cloudflare R2 | 2 | 2 yes [8] | Compatibility is operation-specific; S3 Object Lock APIs are not implemented [1] | [8] [1] |
| Backblaze B2 | 1 | 1 yes [8] | Feature and tool requirements remain separate | [8] |
| Wasabi | 1 | 1 yes [8] | Feature and tool requirements remain separate | [8] |
| IDrive e2 | 1 | 1 yes [8] | Feature and tool requirements remain separate | [8] |
| DigitalOcean Spaces | 2 | 2 yes [8] | The vendor publishes an operation-by-operation compatibility list [2] | [8] [2] |
| Scaleway Object Storage | 3 | 3 yes [8] | Feature and tool requirements remain separate | [8] |
| OVHcloud Object Storage | 5 | 5 yes [8] | Class-specific feature support still varies | [8] |
| Hetzner Object Storage | 1 | 1 yes [8] | Feature and tool requirements remain separate | [8] |
| Akamai Cloud Object Storage | 1 | 1 yes [8] | Feature and tool requirements remain separate | [8] |
| Vultr Object Storage | 5 | 5 yes [8] | The vendor publishes an operation-by-operation compatibility list [3] | [8] [3] |
| Storj | 1 | 1 yes [8] | Feature and tool requirements remain separate | [8] |
| Oracle OCI Object Storage | 3 | 3 yes [8] | Native retention rules are not proof of S3 Object Lock equivalence | [8] |
| Tigris | 4 | 4 yes [8] | Feature and tool requirements remain separate | [8] |
| Filebase | 1 | 1 yes [8] | The current compatibility list omits operations required for an S3 Object Lock target [4] | [8] [4] |
| Telnyx Cloud Storage | 2 | 2 yes [8] | Region-specific Object Lock support remains a separate check | [8] |
Compatibility narrows the offers; the full bill still decides the cost
Protocol compatibility decides which offers qualify. After the required operations, retention controls, region, and backup-tool workflow are verified, the comparison still needs storage, requests, retrieval, temporary-copy storage, and destination-aware egress. [1] [7]
Compatible providers can expose incompatible egress rules. Backblaze B2 publishes a proportional allowance and overage, R2 removes the internet-egress charge but retains request and class-specific retrieval charges, and Wasabi charges no egress fee under a fair-use guideline. [13] [6] [14]
Show the tableas checked 26 July to 12 October 2026
| Provider | S3-compatible? | What a restore costs | Source |
|---|---|---|---|
| Backblaze B2 | Yes, in the offer we checked [8] | Free egress up to 3 times average monthly storage, then $0.01/GB [13] | [8] [13] |
| Cloudflare R2 | Yes, with an operation-by-operation compatibility list [8] [1] | Internet egress not charged; Class A and B operations billed; Infrequent Access retrieval $0.01/GB [6] | [8] [1] [6] |
| Wasabi | Yes, in the offer we checked [8] | Egress not charged; regularly downloading more than you store is outside Wasabi's fair-use guideline [14] | [8] [14] |
| Read-only restore | Requires read and restore operations supported by the selected endpoint [1] | Early deletion: does not apply unless something separately deletes or overwrites the object [7] | [1] [7] |
Sources
Every figure above comes from one of these pages, on the date shown. Each numbered reference in the text links to its entry here. Vendors change prices; if a date looks old, check the source. Three vendors publish a downloadable price feed and the rest are re-checked by hand, which is why the dates are not uniform.
Source pages checked 14 sources
- 1 Cloudflare R2 docs: S3 API compatibility developers.cloudflare.com · checked 26 July 2026
- 2 DigitalOcean docs: Spaces S3 compatibility docs.digitalocean.com · checked 26 July 2026
- 3 Vultr docs: S3 compatibility matrix docs.vultr.com · checked 26 July 2026
- 4 Filebase docs: S3 compatibility matrix filebase.com · checked 26 July 2026
- 5 Amazon S3 docs: Locking objects with Object Lock docs.aws.amazon.com · checked 26 July 2026
- 6 Cloudflare R2 docs: Pricing developers.cloudflare.com · checked 25 July 2026
- 7 AWS: Amazon S3 pricing aws.amazon.com · checked 26 July 2026
- 8 Our price table (all vendors) backupstorageprices.com · checked 25 July 2026
- 9 Google Cloud Storage docs: Interoperability docs.cloud.google.com · checked 11 October 2026
- 10 Google Cloud Storage docs: Rapid Bucket docs.cloud.google.com · checked 11 October 2026
- 11 AWS price list, Frankfurt (S3) pricing.us-east-1.amazonaws.com · checked 22 October 2026
- 12 Google Cloud Storage pricing cloud.google.com · checked 25 October 2026
- 13 Backblaze: B2 API pricing (Class A, B, C, D) www.backblaze.com · checked 25 July 2026
- 14 Wasabi: Pay as you go pricing FAQs wasabi.com · checked 12 October 2026