Cloudflare R2 vs S3 for a SaaS? For most apps, R2 wins on cost because it charges $0 for egress. AWS S3 charges about $0.09/GB to serve data out to the internet; Cloudflare R2 charges nothing, with no threshold. R2 storage is also cheaper ($0.015/GB vs S3's $0.023/GB). S3 still wins for deep AWS-native setups and cold archival tiers — but if your SaaS serves files, images, or downloads to users, R2 is usually the cheaper, simpler choice. It's why Weekendstack ships R2 wired.
Egress is the whole game
Storage costs are similar across providers; what quietly wrecks a bill is egress— the fee to send data out to your users. On S3 that's ~$0.09/GB after a small free tier. On a workload serving 10 TB/month, that's roughly a $900/month difference versus R2's $0 egress — every month, forever. For any app with images, video, user uploads, or downloads, egress dominates, and R2's zero-egress model can be many times cheaper.
When S3 still makes sense
S3 remains ahead if you're deep in AWS (Lambda, tiered storage classes, Object Lambda), or you need cold archival storage where egress is rare. Its ecosystem and integrations are genuinely more mature. If you're not already living in AWS, that maturity mostly buys complexity you don't need yet.
The practical setup for a SaaS
R2 is S3-compatible, so the same SDKs and presigned-URL patterns work. The secure pattern: your server signs a short-lived upload URL, the browser uploads bytes directlyto storage (never proxied through your server), and object keys are scoped per user. That's exactly how Weekendstack does it — presigned PUTs, keys scoped to the authenticated user, no bytes through your API — so uploads are cheap, fast, and safe by default.
Don't want to wire storage, signing, and access scoping by hand? It ships done in Weekendstack. See also the boilerplate comparison.