Storing user uploads, images, videos, and application backups in the cloud is straightforward until you need to choose a storage provider. Amazon S3 is a widely used object storage service with a large ecosystem of AWS integrations. Cloudflare R2 offers S3-compatible storage with no egress bandwidth charges, making it attractive for applications that serve files over the internet.

So, which should you choose? The answer depends on how your application uses files, how often users download them, and which cloud services your backend already relies on. Here’s how AWS S3 vs Cloudflare R2 compares in practice.

What Are AWS S3 and Cloudflare R2?

Amazon Simple Storage Service (S3) stores files as objects inside buckets. Developers use it for application uploads, backups, media libraries, static assets, and data archives. It also integrates with other AWS services for processing, security, analytics, and data management.

Cloudflare R2 is an object storage service designed for unstructured data. It supports an S3-compatible API, so applications can use many existing S3 SDKs and tools with an adjusted endpoint and credentials. Its standout pricing feature is that it does not charge for data transferred directly from R2 to the public internet.

AWS S3 vs Cloudflare R2: Key Differences

1. Storage Costs and Data Transfer

Storage cost is only one part of a cloud storage bill. You also need to consider uploads, downloads, API requests, retrievals, and additional services.

Amazon S3 pricing depends on the AWS Region, storage class, request type, and data transfer pattern. Features such as lifecycle transitions, replication, and certain data management services can introduce additional charges. AWS provides an official S3 pricing breakdown and a pricing calculator to estimate the total cost.

Cloudflare R2 charges for stored data and operations. Its Standard storage rate is currently $0.015 per GB-month, with a monthly free allowance of 10 GB-month of Standard storage, one million Class A operations, and ten million Class B operations. Direct internet egress is free. Infrequent Access storage has different operation charges and a data retrieval fee.

These rates can change, so check the current R2 pricing page before making a budget.

The difference matters most when users download large amounts of data. For example, an application that stores product images and serves them repeatedly may benefit from R2’s egress pricing. An application that processes files primarily inside AWS may find S3’s broader integration more convenient.

2. Which Is Better for File Uploads and Downloads?

Both services can store images, documents, videos, backups, and other application files. The right choice depends on how your application uploads and serves those objects.

For example, a Node.js application could upload a user’s profile image to either service and store the object key in its database. When the image is requested, the application can generate an appropriate URL or use a controlled delivery path.

R2 is appealing when files are frequently downloaded by users because direct internet egress does not incur a bandwidth charge. This can make costs easier to predict for media libraries, downloadable assets, and user-generated content.

S3 is also suitable for these workloads, particularly if you already use AWS for your backend. It provides storage classes and lifecycle features that can help manage data according to how frequently it is accessed.

3. S3 Compatibility Does Not Mean Identical Features

One of R2’s biggest advantages is compatibility with many existing S3 SDKs. In supported applications, migration may require changing the endpoint, access credentials, and configuration rather than rewriting the entire storage integration.

However, S3 compatibility is not a guarantee that every AWS API operation or feature behaves identically. R2 documents unsupported features and implementation differences, including certain bucket-level and object-level operations.

Before moving an existing application, review the R2 S3 API compatibility guide. Test uploads, multipart operations, metadata, presigned URLs, CORS, and any advanced features your code depends on.

This matters especially when an application uses more than basic file uploads and downloads. A migration that looks simple in a small test may require changes if the production application relies on specialized S3 features.

4. Security and Access Control

Both providers offer ways to protect stored objects, but the application still needs a sensible access-control design. Keep private files private, grant applications only the permissions they require, and avoid putting secret access keys in frontend code.

For example, a common pattern is to let the backend authenticate a user and generate a short-lived presigned URL for an authorized upload or download. This avoids making an entire storage bucket public simply to provide access to individual files.

Amazon S3 supports bucket policies, IAM permissions, encryption, versioning, and other data protection features. R2 also supports access credentials and private buckets, with permissions and management options documented by Cloudflare.

Read the official Amazon S3 security best practices and R2 public bucket documentation before exposing files to the internet.

5. When Should You Choose AWS S3?

AWS S3 is often the better choice when:

• Your application already runs on AWS and relies on services that integrate directly with S3.
• You need specific storage classes, lifecycle policies, versioning, replication, or other documented S3 capabilities.
• Your data workflow uses AWS analytics, processing, or backup services.
• You need to match an existing architecture that already uses S3 APIs and permissions.

In these situations, using S3 can simplify integration and reduce the number of separate systems your team has to manage.

6. When Should You Choose Cloudflare R2?

R2 is worth considering when:

• Your application serves large amounts of downloadable content over the internet.
• You want to avoid direct internet egress charges on stored objects.
• Your existing application can work with R2’s supported S3-compatible API.
• You plan to use Cloudflare Workers or other Cloudflare services alongside object storage.

R2 can be particularly attractive for user uploads, image libraries, downloads, and application assets. Still, estimate storage and operation costs, and verify compatibility before migrating a production workload.

Final Verdict

In the AWS S3 vs Cloudflare R2 comparison, S3 is a strong choice for applications that rely on AWS integrations and its broader collection of storage features. R2 is especially attractive when internet downloads make egress charges a significant part of the storage bill.

Do not choose based on the storage price alone. Estimate your stored data, read and write operations, downloads, retention requirements, and integration needs. If you already use AWS extensively, S3 may be the simpler option. If your application mainly stores and serves files and wants predictable egress costs, R2 deserves a close look.