Best File Upload and Storage APIs for Web Apps Under $50/Month

Every web app eventually faces the same question: where do user uploads live, and how much will it cost to store and serve them? For teams operating under $50/month, the answer isn't always AWS S3. A crop of S3-compatible, zero-egress, and even decentralized alternatives has made cheap file storage more competitive than ever — and the things actually worth buying depend heavily on your app's traffic patterns and stack.

This guide compares the best file upload and storage APIs for web apps on a budget. We evaluated each option on three dimensions that matter most: storage cost per GB, egress (download) fees, and ease of integration — including whether the API is S3-compatible or proprietary, whether a CDN is built in, and how generous the free tier is.

How We Compared

1. Backblaze B2 — Best Overall Value

Backblaze B2 offers S3-compatible cloud storage at approximately $0.006/GB/month for storage and $0.01/GB for downloads, with a 10GB free tier to get started.1 The full S3-compatible API means you can swap out AWS S3 with minimal code changes — existing SDKs, CLI tools, and libraries work out of the box.5

The real trick is pairing B2 with Cloudflare's CDN. Through the Bandwidth Alliance, data transferred from Backblaze B2 to Cloudflare is free — effectively giving you zero-egress delivery at rock-bottom storage prices.5 For a web app storing 500GB of user uploads with moderate traffic, you'd pay roughly $3/month for storage plus whatever Cloudflare charges for your plan (the free tier may suffice). That's well under the $50 ceiling.

Verdict: If you want the lowest raw storage cost and don't mind wiring up your own CDN, B2 is hard to beat.

2. Supabase Storage — Best Developer Experience

Supabase Storage provides a file upload API with built-in CDN delivery, row-level security (RLS) policies, and tight integration with Supabase's authentication and database layers.2 The free tier includes 1GB of storage, and the Pro plan at $25/month bumps that to 100GB.2

Where Supabase shines is the end-to-end pipeline. You define storage policies in SQL alongside your database schemas, authenticate uploads with the same JWT your app already uses, and serve files through a global CDN — all within one platform. For full-stack teams already building on Supabase's Postgres backend, adding file storage is almost frictionless.

The tradeoff is cost at scale: at $25/month for 100GB, the effective rate is $0.25/GB — significantly higher than B2 or R2. But for apps that value integrated auth, RLS, and a polished dashboard over raw price-per-GB, the convenience tax is worth it.

Verdict: The best choice if you're already in the Supabase ecosystem or want upload-to-delivery handled in one platform.

3. Cloudflare R2 (Pages Ecosystem) — Best for Zero-Egress Delivery

Cloudflare R2 is S3-compatible object storage priced at $0.015/GB/month with zero egress fees — you pay nothing for data leaving R2, ever.3 The free tier includes 10GB of storage.3 When paired with Cloudflare Pages, uploaded assets are distributed globally at the edge, making R2 ideal for serving user-generated images, videos, and static files to a worldwide audience.

The math is compelling for read-heavy apps. If your users download 1TB of files per month, R2 charges $0 for that bandwidth. The same traffic on Backblaze B2 would cost $10 in egress (before Bandwidth Alliance credits), and on AWS S3 it could run $90+. Storage costs are slightly higher than B2 ($0.015 vs. $0.006 per GB), but for apps where downloads dwarf storage, R2's zero-egress model wins decisively.

Verdict: Unbeatable for apps with high read volume or global audiences where egress would otherwise dominate the bill.

Honorable Mentions

Aleph Cloud takes a fundamentally different approach: block storage and indexing on a distributed network with no single point of failure.4 Its pay-per-use model is often cheaper than centralized providers, and the decentralized architecture appeals to apps that prioritize censorship resistance and data sovereignty.4 For most conventional web apps it's a niche choice — the API isn't S3-compatible and the tooling ecosystem is smaller — but for Web3-adjacent infrastructure or data-sovereignty requirements, it offers something no centralized provider can match.

Oracle Cloud's Always Free tier is worth noting for hobby projects: it includes 200GB of block storage and 20GB of object storage free forever, with no credit card required for basic usage.6 It won't power a production app with real traffic, but for proof-of-concept work it's hard to argue with zero cost.

The Bottom Line

Under $50/month, the right choice comes down to your app's dominant cost driver:

• Lowest storage cost → Backblaze B2 at $0.006/GB, especially paired with Cloudflare's CDN for near-zero egress.1
• Best developer experience → Supabase Storage, with integrated auth, RLS, and CDN for $25/month.2
• Zero egress → Cloudflare R2, which eliminates download fees entirely.3
• Decentralization → Aleph Cloud, for apps that need distributed, censorship-resistant storage.4

For the majority of web apps, the Backblaze B2 + Cloudflare CDN combination delivers the best balance of cost, compatibility, and reliability. If you're already on Supabase, stay there — the convenience is worth the premium. And if egress is your bottleneck, R2's zero-egress model pays for itself fast.

Disclosure: We may earn affiliate commissions from some of the providers listed above. This does not influence our rankings or recommendations.

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