RDS vs Aurora

Overview

Amazon RDS and Amazon Aurora are both managed relational database services on AWS, and Aurora is technically offered within the RDS family. The practical distinction is the engine. RDS runs standard, off-the-shelf database engines, while Aurora is a cloud-native engine AWS built for MySQL and PostgreSQL compatibility, with a distributed storage layer designed for higher performance and availability.

Key Differences

RDS provides managed versions of familiar engines: MySQL, PostgreSQL, MariaDB, Oracle, and SQL Server. AWS handles patching, backups, and Multi-AZ failover with a standby replica. This breadth matters when you need a specific engine, especially commercial databases like Oracle or SQL Server that Aurora does not offer. RDS performance is solid and predictable, and for modest or steady workloads it is generally the more economical choice.

Aurora keeps MySQL and PostgreSQL wire compatibility but replaces the storage engine with a distributed, fault-tolerant layer that replicates data six ways across three Availability Zones. This architecture delivers higher throughput than standard engines, faster crash recovery, and very high durability. Aurora supports up to fifteen low-latency read replicas that share the same storage, making read scaling and failover faster and more robust than typical RDS replicas. Storage auto-scales as data grows. The trade-off is cost: Aurora's per-hour pricing is higher, and it is limited to MySQL/PostgreSQL compatibility.

In short, RDS offers engine choice and lower cost for ordinary workloads, while Aurora offers superior performance, availability, and read scaling for MySQL- and PostgreSQL-compatible applications.

When to Choose RDS

Choose RDS when you need a specific engine, particularly Oracle, SQL Server, or MariaDB, or when your workload is modest and cost-sensitive. Standard-engine compatibility and lower pricing make RDS the pragmatic default for many applications that do not require Aurora's advanced scaling.

When to Choose Aurora

Choose Aurora for demanding MySQL- or PostgreSQL-compatible workloads that need high throughput, strong availability, fast failover, and many read replicas. Its distributed storage and automatic scaling suit high-traffic, mission-critical applications where performance and resilience justify the higher cost.

Verdict

RDS and Aurora share the same managed-database umbrella but target different needs. Use RDS for engine flexibility and cost efficiency on ordinary workloads, and Aurora when you want a cloud-native, high-performance, highly available engine for MySQL or PostgreSQL. For compatible workloads at scale, Aurora often wins on performance and resilience; for everything else, standard RDS engines are frequently the better value.