Simple, usage-based pricing
No subscriptions. No base fees. Pay for what you use — per request and per GB processed. All rates include encryption.
Free
$0/mo
For evaluation and local development.
- 10K write requests
- 100K read requests
- 10GB processed
- 2 plugin slots
- Detect & redact plugins
- Community support
Usage
$0/mo base
No caps. Bill for overage only.
- Everything in Free
- No usage limits
- Envelope encryption
- Stable encryption
- Cross-cloud mirroring
- 8 plugin slots
- Email support
PAYG rates
| Metric | Free /mo | PAYG rate | Example: 500K writes, 2M reads, 50GB |
|---|---|---|---|
| Write requests | 10K | $15 / 1M | $7.35 |
| Read requests | 100K | $1 / 1M | $1.90 |
| Data processed | 10GB | $0.10 / GB | $4.00 |
| Total | $13.25 | ||
Estimate your cost
FAQ
What counts as a write request?
PUT, COPY, and DELETE operations through the S4 gateway. Each one runs your plugin pipeline — regardless of object size. The GB charge covers the data volume.
What counts as a read request?
GET, HEAD, and LIST operations. Reads are cheaper because they typically don't run the full plugin pipeline (decrypt only if needed).
Do you charge for storage?
No. S4 never stores your data. You bring your own S3-compatible storage — AWS S3, Backblaze B2, Cloudflare R2, Google Cloud Storage, MinIO, or any S3-compatible endpoint. You pay your storage provider directly.
Is encryption included in the write rate?
Yes. All plugin pipelines — including RSA-OAEP envelope encryption and AES-GCM — are included at the flat write rate. No per-plugin surcharges.
What happens when I exceed the free tier?
Free tier users are soft-capped at the allowance. Upgrade to PAYG by adding a payment method, and you'll only be charged for usage above the free allowance. Paying customers are never hard-blocked.
How does cross-cloud mirroring work?
S4 dual-writes objects to multiple S3-compatible backends using consistent hashing. $50/mo per additional destination includes the mirroring infrastructure. Active/passive and active/active read modes supported.
Can I self-host S4?
Yes. S4 is open source (Apache 2.0). You can run the gateway in your own infrastructure — same plugins, same pipeline, zero S4 cloud costs. The hosted version adds convenience, not lock-in.
Start with 10K free writes per month
No credit card required. Upgrade when you need more.
Get Started Free