For a low-traffic project, the cheapest Postgres setup is one that stops billing for compute when nothing is hitting it. Fixed-size cloud Postgres charges 24/7 even when your app sees one request a day. Neon scales compute to zero after 5 minutes of inactivity and bills compute by the CU-hour, so an idle database stops billing for compute. Storage is still metered at $0.35/GB-month.
What you pay on Neon
The Free plan covers most side projects:
- 100 projects, 10 branches per project
- 0.5 GB storage per project
- 100 CU-hours of compute per month (enough to run 0.25 CU for ~400 hours)
- Scale to zero after 5 minutes (always on, can't disable)
If your app is busier than the Free plan allowance, the Launch plan bills compute at $0.106/CU-hour and storage at $0.35/GB-month. There's no monthly minimum.
A small worked example
Say your app gets traffic for about 2 hours of active compute time per day. Active means the compute is actually running, not suspended.
| Resource | Usage | Cost |
|---|---|---|
| Compute | 0.25 CU × 60 active hours | 15 CU-hours × $0.106 = $1.59 |
| Storage | 1 GB root branch | 1 × $0.35 = $0.35 |
| Total | ~$1.94/month |
If the same project fits inside Free plan limits (100 CU-hours, 0.5 GB), it's $0.
Cap your spend
On Launch and Scale plans, set a spending limit so an unexpected traffic spike doesn't surprise you. You'll get alerts at 80% and 100%.
How this compares to other low-traffic options
| Provider | Free tier | Paid baseline | Idle behavior |
|---|---|---|---|
| Neon | 100 CU-hours/month, 0.5 GB/project | $0.106/CU-hour, no monthly minimum | Scales to zero after 5 min idle (docs) |
| Supabase Free Plan | 2 projects, 500 MB per project | Pro Plan from $25/month + $10 compute per extra project (docs) | Free Plan projects pause after inactivity; paid projects run 24/7 (docs) |
| Aurora Serverless v2 (PostgreSQL) | None | Per-ACU-hour billing | Scales to 0 ACUs (auto-pause) on Aurora PostgreSQL 13.15+/14.12+/15.7+/16.3+ (docs) |
| RDS for PostgreSQL | 750 hrs/month db.t3.micro for 12 months (AWS Free Tier) | Per-instance hourly | No auto-pause; pays 24/7 |
For a hobby project with one request a day, the cheapest options are Neon's Free plan (no compute fees while idle) or Supabase's Free plan (the project pauses, restored on demand within 90 days). Aurora Serverless v2 with min ACU of 0 is competitive once you outgrow free tiers but is more involved to set up than either Neon or Supabase.
Start on the Free plan. Upgrade only when you hit the limits.