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Databases · head to head

Memcached vs PostgreSQL

M

Memcached

Databases

Distributed memory object caching system

From
Free
Rated
-
Full reviewWebsite
PostgreSQL logo

PostgreSQL

Databases

The world's most advanced open source relational database

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Memcached no persistence at all: restart a node and its cache is gone, which every design must assume; PostgreSQL requires manual scaling across multiple machines for very large deployments
  • They diverge on capability: Memcached covers In-memory key-value cache, PostgreSQL covers ACID Compliance.
  • Prices and features above were last checked on 1 September 2026.

Where they differ

Only the attributes on which Memcached and PostgreSQL actually diverge.

Attributes where Memcached and PostgreSQL differ
AttributeMemcachedPostgreSQL
Pricing modelOpen source, no licence fee; managed cloud billed separatelyUnknown
PlatformsLinux, macOS, Windows, Docker, Self-hostedLinux, Windows, macOS, BSD, Unix
FoundedUnknown1996

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated), category (Databases).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Memcached

  • In-memory key-value cache
  • Multithreaded
  • Client-side sharding
  • Predictable memory use

Only in PostgreSQL

  • ACID Compliance
  • JSON/JSONB Support
  • Full-text Search
  • Extensibility
  • Advanced Indexing
  • Partitioning
  • Replication
  • pgAdmin

What people use each for

The jobs each tool is most often brought in to do.

Memcached

  • Caching expensive database query results to cut loadnot PostgreSQL
  • Session storage where losing sessions on restart is acceptablenot PostgreSQL
  • Fronting an API whose responses are costly and change slowlynot PostgreSQL

PostgreSQL

  • Transaction processingnot Memcached
  • Data storagenot Memcached
  • Application backendnot Memcached
  • Reportingnot Memcached
  • Data analyticsnot Memcached

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Memcached

  • No persistence at all: restart a node and its cache is gone, which every design must assume
  • No replication or failover, so losing a node loses that share of the cache
  • Only simple key-value, with none of the lists, sorted sets or streams Redis offers
  • Values are capped at 1MB by default, which surprises teams caching large documents

PostgreSQL

  • Requires manual scaling across multiple machines for very large deployments
  • Performance tuning requires deep knowledge of database internals
  • No built-in graphical admin interface; command-line tools are primary method

Pricing, plan by plan

Memcached

Free
  • MemcachedFree
    • Full functionality
    • Self-hosted
    • No usage limits

PostgreSQL

Free

No published plan breakdown. See the PostgreSQL review.

Which should you pick?

Choose Memcached if

  • You need in-memory key-value cache.
  • You want to start without paying.
  • You work on Linux, macOS, Windows, Docker, Self-hosted.
  • You also want multithreaded.
Memcached review

Choose PostgreSQL if

  • You need acid compliance.
  • You want to start without paying.
  • You work on Linux, Windows, macOS, BSD, Unix.
  • You also want json/jsonb support.
PostgreSQL review

Questions people ask

Is Memcached or PostgreSQL better?
Neither clearly leads. Memcached starts at Free and PostgreSQL at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Memcached or PostgreSQL?
Memcached starts at Free and PostgreSQL at Free.
Does Memcached or PostgreSQL run on more platforms?
Memcached runs on Linux, macOS, Windows, Docker, Self-hosted. PostgreSQL runs on Linux, Windows, macOS, BSD, Unix.
Can I use Memcached for free?
Both have a free tier, so you can try either at no cost before committing.
What is Memcached best used for?
Memcached is most often used for caching expensive database query results to cut load, session storage where losing sessions on restart is acceptable, fronting an api whose responses are costly and change slowly. Of those, caching expensive database query results to cut load and session storage where losing sessions on restart is acceptable are not what PostgreSQL is typically brought in for.
What can Memcached do that PostgreSQL cannot?
Memcached covers In-memory key-value cache, Multithreaded, Client-side sharding, Predictable memory use. PostgreSQL covers ACID Compliance, JSON/JSONB Support, Full-text Search, Extensibility.

Answered from the vendors’ own pages

Memcached: Is Memcached free?

Yes, open source with no licence fee.

PostgreSQL: Is PostgreSQL completely free?

Yes. PostgreSQL is completely free and open source with no licensing fees or restrictions on use.

Source
Memcached: Memcached or Redis?

Memcached is a pure cache: simpler, multithreaded and very predictable. Redis adds persistence, replication and rich data structures, which is why it is the default choice unless you specifically want a cache and nothing more.

PostgreSQL: What platforms does PostgreSQL run on?

PostgreSQL runs on all major operating systems including Linux, Windows, macOS, BSD, and commercial Unix variants, and has been proven highly scalable managing terabytes to petabytes of data.

Source
Memcached: Does Memcached persist data?

No. Everything is in memory and lost on restart, by design.

PostgreSQL: What procedural languages are supported?

PostgreSQL supports stored functions and procedures in multiple languages including PL/pgSQL, Perl, Python, Tcl, Java, JavaScript, R, and Rust.

Source
PostgreSQL: What is ACID compliance in PostgreSQL?

PostgreSQL has been ACID-compliant since 2001, ensuring data integrity through atomicity, consistency, isolation, and durability guarantees for all transactions.

Source
PostgreSQL: Does PostgreSQL support JSON data?

Yes. PostgreSQL supports JSON and JSONB data types for storing and querying JSON documents, along with XML and other document formats.

Source
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