# Amazon RDS vs Prisma Postgres

Canonical: https://inetgeek.com/compare/amazon-rds-vs-prisma-postgres/

Every value below is read from Amazon RDS's and Prisma Postgres's own documentation. See https://inetgeek.com/methodology/ for how.

## At a glance

| Criterion | Amazon RDS | Prisma Postgres |
| --- | --- | --- |
| Managed connection pooling | Supported | Supported |
| Engine | PostgreSQL, alongside MySQL, MariaDB, Oracle, SQL Server and Db2. Each engine is a separate RDS product with its own version list and its own feature support, so a capability documented for one is not a capability of RDS as a whole. | PostgreSQL. |
| Connection limit | Not a fixed number: RDS for PostgreSQL sets max_connections by formula from the instance's memory — LEAST({DBInstanceClassMemory/9531392}, 5000) — so a bigger instance class gets more connections and the ceiling is 5,000 however large it is. The parameter can be set by hand anywhere from 6 to 262,143, which is a limit on what you may configure rather than what an instance will serve. Other engines use different divisors: MySQL is memory/12582880 with no cap. | 100 pooled connections on Starter and 10 direct; 10 pooled on Free, 500 on Pro and 1,000 on Business. |
| Backup retention | Between 0 and 35 days, set per DB instance; 0 disables automated backups entirely. The default depends on how the instance was created — one day via the API or CLI, seven days via the console — so there is no single default to quote. Multi-AZ DB clusters cannot be set below 1 day. | Daily backups with 7-day retention on Starter and Pro, 30 days on Business. The free plan has none. |

## Where they differ

### Engine

- Amazon RDS: PostgreSQL, alongside MySQL, MariaDB, Oracle, SQL Server and Db2. Each engine is a separate RDS product with its own version list and its own feature support, so a capability documented for one is not a capability of RDS as a whole. ([source](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_PostgreSQL.html))
- Prisma Postgres: PostgreSQL. ([source](https://www.prisma.io/pricing))

### Connection limit

- Amazon RDS: Not a fixed number: RDS for PostgreSQL sets max_connections by formula from the instance's memory — LEAST({DBInstanceClassMemory/9531392}, 5000) — so a bigger instance class gets more connections and the ceiling is 5,000 however large it is. The parameter can be set by hand anywhere from 6 to 262,143, which is a limit on what you may configure rather than what an instance will serve. Other engines use different divisors: MySQL is memory/12582880 with no cap. ([source](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_Limits.html))
- Prisma Postgres: 100 pooled connections on Starter and 10 direct; 10 pooled on Free, 500 on Pro and 1,000 on Business. ([source](https://www.prisma.io/pricing))

### Backup retention

- Amazon RDS: Between 0 and 35 days, set per DB instance; 0 disables automated backups entirely. The default depends on how the instance was created — one day via the API or CLI, seven days via the console — so there is no single default to quote. Multi-AZ DB clusters cannot be set below 1 day. ([source](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_WorkingWithAutomatedBackups.BackupRetention.html))
- Prisma Postgres: Daily backups with 7-day retention on Starter and Pro, 30 days on Business. The free plan has none. ([source](https://www.prisma.io/pricing))

## Which should you choose?

Pick Amazon RDS if Teams already inside AWS, where the database sitting in the same VPC as everything else is worth more than any single feature on this page. Six engines, up to 35 days of point-in-time recovery, and read replicas you create and delete yourself.

Pick Prisma Postgres if Prisma ORM users who want the database and the client from one vendor, with a pooled connection limit stated per plan rather than left to be discovered.

Consider something else: Amazon RDS — You want a database per pull request. RDS documents no branching, and replicas are manual — AWS states outright that it does not autoscale them.

Consider something else: Prisma Postgres — Four separate meters — requests, memory, vCPU and bandwidth — sit on top of the plan fee, so the monthly number is a floor rather than a bill.

## Documented by only one

- Free tier: Prisma Postgres: Yes
- Entry paid plan: Prisma Postgres: $10/month for Starter. Pro is $49 and Business $129, each including a larger request allowance.
- Pricing model: Prisma Postgres: A plan fee plus usage: requests, memory GB-hours, active vCPU-hours and outbound bandwidth are each metered — $1 per million requests beyond the allowance, $0.006 per GB-hour, $0.064 per vCPU-hour, $0.025 per GB out.
- Startup credit program: Prisma Postgres: Prisma for Startups: database bill covered up to $10,000 for one year, plus 1:1 guidance. Venture-funded track requires pre-seed/seed/Series-A funding raised in the last 12 months and founded in the last 5 years; bootstrapped track requires ≥5k MRR for 6 months and 2 full-time team members.
- Storage (entry plan): Prisma Postgres: 500 MB on the free plan across 50 databases. Paid plans raise the database count to 1,000 and beyond.
- When idle: Prisma Postgres: Scales to zero when idle, and Prisma states an idle app costs nothing.
- Point-in-time recovery: Amazon RDS: Any point inside the configured backup retention period, so up to 35 days. Transaction logs are uploaded to S3 every five minutes, which is what bounds how close to now the latest restorable time can be.
- Read replicas: Amazon RDS: Supported — 15 per primary, raisable on request
- SOC 2: Amazon RDS: Listed as SOC-compliant on AWS's own compliance scope page.
- ISO 27001: Amazon RDS: Covered under AWS's account-wide ISO/IEC 27001:2022 certification — not scoped per-service the way SOC, HIPAA and PCI DSS are on AWS's own site.
- HIPAA: Amazon RDS: Listed as a HIPAA-eligible service on AWS's own reference page.
- GDPR / data residency: Amazon RDS: AWS customers can process personal data on all AWS services in compliance with GDPR, and choose the storage type and geographic region for their data.
- PCI DSS: Amazon RDS: Listed as PCI DSS-compliant on AWS's own compliance scope page.

## Questions this comparison answers

**Should I choose Amazon RDS or Prisma Postgres?**

Pick Amazon RDS if Teams already inside AWS, where the database sitting in the same VPC as everything else is worth more than any single feature on this page. Six engines, up to 35 days of point-in-time recovery, and read replicas you create and delete yourself.
Pick Prisma Postgres if Prisma ORM users who want the database and the client from one vendor, with a pooled connection limit stated per plan rather than left to be discovered.