Databases are bought three ways: as free software you run yourself, as a cloud service billed by the hour or request, and as a commercial licence counted in cores.
This guide ranks twelve engines on first-ninety-day effort, price once real workloads arrive, how data leaves, and whether you can run it without a vendor.
Vendors can pay for visibility on this page. It never changes what an entry
says about a product, including the criticism, and we earn nothing when you click through to a
vendor. How that works.
In short
What database management systems do
A database management system stores and retrieves an application's data, enforces transactions and access rights, and offers a query language so programs and people can work with it.
In this order: setup effort, what it really costs, how your data comes back out, whether
you can leave, and who each database management system is built for. One rule sits on top of those tests:
Places 1 to 3 go to challengers, vendors outside the best-known brands in a category, wherever the category has them; the established names follow from place 4 in their ranked order. Why those five, and why there is no
score out of ten, is on the how we work page.
Per request or provisioned capacity, published; monthly free allowance
—
AWS-based teams wanting a database with no servers to patch
Teams needing joins, ad hoc SQL or a multi-cloud exit
Country is where the vendor is headquartered or contracts from, which is a
different question from where your data is hosted. Where the two tell different stories, the
entry says so.
Community-run relational engine under a permissive licence, no vendor involved
Ranked #1 of 12 in Best Database Management Systems in 2026.
Free tierOpen sourcePublished pricingElsewhere
The first ninety days are mostly choosing a host or support company from the project's published lists, then testing the upgrade path. Staying current is a yearly decision, since each major version is supported for five years and the final minor release marks the end.
Exit is the easiest in this list: pg_dump exports a database consistently without blocking readers or writers, and the licence has no clause that charges for leaving.
What stands out
Open source, permissive licence
Community governed
Five-year support window
Where it costs you
Support and hosting must be sourced from third parties, because the project has no single vendor
Major upgrades need a dump and reload or pg_upgrade rather than an in-place patch
Right for
Teams that want a relational engine with no vendor able to reprice it
Wrong for
Buyers wanting one company accountable for support and uptime
Not stated by the vendorFree to use under the PostgreSQL Licence; hosting and support bought separately
MySQL-derived server kept under GPLv2 by a non-profit foundation
Ranked #2 of 12 in Best Database Management Systems in 2026.
Free tierOpen sourcePublished pricingNorth America
MariaDB splits into a foundation that keeps the server GPLv2 and a company that sells MariaDB Cloud, so check which of the two you are signing with.
The cloud pricing page lists Foundation, Power and PowerPlus tiers, each with its own compute and storage ceilings. Running the server yourself keeps the GPLv2 terms, but backups, replication and patching then fall to your own staff.
What stands out
Open source (GPLv2)
Foundation governed
Managed cloud option
Where it costs you
The hosted service comes from the commercial MariaDB company, separate from the foundation that governs the server
The lowest cloud tier is limited to 16 vCPU, 128 GB RAM and 1000 GB of storage
Right for
Teams moving from MySQL who want GPL terms and foundation governance
Wrong for
Buyers who need one organisation to run and support it
United StatesFree server under GPLv2; MariaDB Cloud billed per hour, published
Serverless database in one file, with public domain source code
Ranked #3 of 12 in Best Database Management Systems in 2026.
Free tierOpen sourcePublished pricingNorth America
SQLite removes the database server from the budget, which is its whole case. Setup is a library and a file, and exit is copying that file between operating systems.
The limits are stated on its own site: 281 terabytes maximum size, unlimited readers, one writer. Paid support starts from a yearly subscription, and a warranty of title is sold for companies whose lawyers want a licence on paper.
What stands out
Embedded
Open source, public domain
Single file
Where it costs you
It allows one writer at any instant, so write-heavy or multi-server workloads need another engine
The project accepts patches only from contributors who have signed a public domain affidavit
Right for
Applications, devices and small sites that need storage inside the app
Wrong for
Systems with many machines writing to one shared database
United StatesFree, public domain; paid support and warranty of title priced on a published list
Distributed SQL database sold per vCPU-hour, with a revenue-capped free licence
Ranked #4 of 12 in Best Database Management Systems in 2026.
Self-hostablePublished pricingNorth America
The cloud pricing page shows two tiers: Standard on shared infrastructure and Mission Critical on dedicated infrastructure with a higher availability target. A 30-day trial brings 400 in credit, and Mission Critical asks for a credit card.
Multi-region storage is replicated, so the pricing page's own example counts 100 GiB as 450 GiB billed. Plan the bill around storage and backups as well as compute.
What stands out
Distributed SQL
Per vCPU-hour
Software licence
Where it costs you
Billing follows provisioned vCPUs, so an idle cluster is still charged
Self-hosted use beyond the free licence needs a paid Enterprise licence, and unsent telemetry throttles clusters after 7 days
Right for
Teams needing SQL that stays available across regions or clouds
Wrong for
Small applications where one PostgreSQL server is enough
United StatesCloud billed per vCPU-hour, published; self-hosted licence free below a revenue limit
Document database sold mainly as Atlas cloud, with a source-available server
Ranked #5 of 12 in Best Database Management Systems in 2026.
Free tierPublished pricingNorth America
The cheapest path is Atlas: a 512 MB cluster to learn on, Flex at up to 30 a month with 5 GB storage, then Dedicated clusters from 10 GB. Search, vector search and stream processing are separate priced services, so the bill grows with each feature adopted.
The server's licence is the SSPL, written by MongoDB,, and section 13 requires releasing the service source code if you offer it to third parties.
What stands out
Document model
SSPL server
Atlas cloud
Where it costs you
Offering the community server as a service triggers the SSPL duty to release the service source code
Enterprise Advanced pricing is not listed, so self-managed buyers must ask sales
Right for
Teams building around JSON documents who prefer a managed cloud service
Wrong for
Buyers who need an OSI-approved licence for the server
United StatesFree Atlas cluster of 512 MB; Flex and Dedicated billed by the hour, published
Memory-first data store used for caching, queues and sessions, now tri-licensed
Ranked #6 of 12 in Best Database Management Systems in 2026.
Free tierPublished pricingNorth America
For an application already on Redis, vector search over existing fields avoids adding another service. The docs describe vector fields and search inside Redis, and the pricing page notes a Flex option that holds data at 10% RAM to cut cost.
The weak point is economics at scale: memory is the main price driver, and the licence for new code is a choice among three terms, only one of which is AGPL.
What stands out
In-memory
Tri-licensed
Cache and sessions
Where it costs you
The free database is limited to 30 MB on a shared deployment with community support
Redis 8 code is offered under RSALv2, SSPL or AGPLv3, which restricts some commercial uses
Right for
Teams already running Redis who want vector queries beside their cache
Wrong for
Buyers who need cheap storage for very large vector collections
United StatesFree cloud database of 30 MB; Essentials hourly, Pro from a monthly minimum
Masterless wide-column database for large write volumes across several machines
Ranked #7 of 12 in Best Database Management Systems in 2026.
Free tierOpen sourcePublished pricingNorth America
There is nothing to buy: the Apache Licence 2.0 covers the code, and the project lists a 5.0 line plus a maintained 4.1 line, with the latest 4.1 release dated 7 August 2026. The cost is people.
Model tables around queries, run several nodes, and plan upgrades yourself. The project states you can add or remove nodes without downtime, so growth is a hardware and staffing decision.
What stands out
Masterless
Open source (Apache 2.0)
Multi-node
Where it costs you
CQL has no joins or sub-queries, so data models are built per query
Running one node loses the point of Cassandra, so a useful setup needs several machines
Right for
Teams writing very large volumes across data centres, with staff to operate it
Wrong for
Small applications needing joins and a single inexpensive server
United StatesFree to run under Apache Licence 2.0; no vendor sells it
JSON document database with SQL++ queries, sold as Capella or as Server
Ranked #8 of 12 in Best Database Management Systems in 2026.
Free tierPublished pricingNorth America
Couchbase sells four Capella tiers: Free, Basic from a per-node hourly rate, Developer Pro with an 8-hour response, and Enterprise with a 30-minute response and customer-managed keys. Credits cover data, query and search services.
Couchbase Mobile adds embedded offline-first storage with sync. Check the node count first: the Enterprise tier's three-node floor, multiplied by the hourly rate and the hours in a month, sets the real starting price rather than the headline per-node figure.
What stands out
SQL++ queries
Per node-hour
Mobile sync
Where it costs you
The free Capella cluster has forum support only
Enterprise Capella needs a three-node minimum, and Server and Mobile prices are not listed
Right for
Teams wanting SQL++ over JSON documents plus mobile sync from one vendor
Wrong for
Buyers who want fully published self-managed prices up front
United StatesFree Capella cluster; paid Capella tiers per node-hour, published; Server on request
Oracle-owned relational server, free under GPLv2, paid editions on request
Ranked #9 of 12 in Best Database Management Systems in 2026.
Open sourcePublished pricingNorth America
MySQL's GitHub licence file states Community Server is GPLv2 and comes from the MySQL team at Oracle. Paid options are Enterprise Edition, plus Standard, Classic and NDB Cluster editions named in the menu, and HeatWave on Oracle's price list per ECPU-hour.
Ask Oracle for a written quote that names the edition and the cloud or on-premises route, because the page itself shows no prices.
What stands out
Oracle-owned
Open source community edition
HeatWave cloud
Where it costs you
The product page lists no prices for Enterprise Edition
The code is released by one company, Oracle, which also sells the paid editions
Right for
Teams running widely supported web stacks who accept Oracle as owner
Wrong for
Buyers who want vendor-neutral governance of the code
United StatesCommunity Server free under GPLv2; HeatWave metered per ECPU-hour; Enterprise on request
Windows and Linux database licensed per core, with free Express edition
Ranked #10 of 12 in Best Database Management Systems in 2026.
Published pricingNorth America
Microsoft lists SQL Server 2022 prices per two-core pack for Enterprise and Standard, with a cheaper server plus CAL route for Standard, and a pay-as-you-go option through Azure Arc.
Developer and Express are free downloads. SQL Server 2025 is supported on Red Hat and Ubuntu as well as Windows. Count cores and client licences before signing, and compare them with the edition limits above.
What stands out
Per-core licence
Windows and Linux
Edition limits
Where it costs you
Standard edition is capped at 4 sockets or 32 cores, and Express at 50 GB per database
Licence counts follow cores or client access licences, so sizing mistakes raise the bill
Right for
Organisations with Microsoft licensing, staff and Windows or Linux servers in place
Wrong for
Teams that want to avoid counting cores and client licences
United StatesPer core or server plus client licences, list prices published; Express and Developer free
Commercial enterprise database, now branded Oracle AI Database, with capped free edition
Ranked #11 of 12 in Best Database Management Systems in 2026.
Published pricingNorth America
The free edition's caps of 2 CPU threads, 2 GB RAM and 12 GB of data leave room for small workloads only.
Larger deployments go through the technology price list, or through the cloud, Exadata and Autonomous options on OCI, Azure, Google Cloud and AWS. Ask in writing how the licence metric applies to your servers before the first ninety days begin.
What stands out
Enterprise licence
Free edition capped
AI Database branding
Where it costs you
The free edition is capped at 2 CPU threads, 2 GB of RAM and 12 GB of user data
Beyond those caps, prices sit in a separate downloadable list, not on the product page
Right for
Large organisations already tied to Oracle licensing, tooling and staff
Wrong for
Small teams that need cheap, portable and simple setup
United StatesLicence price list published as PDF; Oracle Database Free for development within caps
AWS key-value and document database billed per request or provisioned capacity
Ranked #12 of 12 in Best Database Management Systems in 2026.
Published pricingNorth America
DynamoDB offers on-demand billing in read and write request units and a provisioned mode with reserved capacity. The free allowance covers 25 read and 25 write units, 25 GB and two-Region global table writes.
Exports to S3 do not consume read capacity. The downloadable local version exists so developers can test without the web service; production runs on AWS. Compare the two billing modes on your own traffic before choosing one.
What stands out
AWS only
On-demand or provisioned
Key-value access
Where it costs you
It runs only on AWS, so moving away means rewriting the data access layer
Costs follow request volume and capacity mode, so a bill cannot be forecast without a traffic estimate
Right for
AWS-based teams wanting a database with no servers to patch
Wrong for
Teams needing joins, ad hoc SQL or a multi-cloud exit
United StatesPer request or provisioned capacity, published; monthly free allowance
A database management system stores and retrieves an application's data, enforces transactions and access rights, and offers a query language so programs and people can work with it. The differences that matter are rarely in the feature list, so this is
the order we would work through them.
01
Decide whether you need a published price
12 of the 12 tools here publish what they cost; the other 0 quote per organisation. The ones you can compare without a sales call: PostgreSQL, MariaDB, SQLite, CockroachDB, MongoDB, Redis, Apache Cassandra, Couchbase, MySQL, Microsoft SQL Server, Oracle Database, Amazon DynamoDB.
02
Decide how much the jurisdiction matters
These 12 vendors are established in 2 countries across 2 regions (North America 11, Elsewhere 1). That decides whose disclosure law applies to what the vendor holds, wherever the servers are.
03
Consider whether you want the source
5 of these are open source: PostgreSQL, MariaDB, SQLite, Apache Cassandra, MySQL. Hosting one yourself trades a subscription for maintenance.
Running it yourself or buying a managed service
Most buyers here are choosing between operating an engine and paying someone else to. PostgreSQL, MariaDB, SQLite and Apache Cassandra cost nothing to licence, but you carry backups, upgrades and security. MongoDB sells mainly through Atlas, which starts with a 512 MB cluster and moves to hourly billing.
Amazon DynamoDB has no server to run, but it exists only inside AWS. MariaDB offers both routes: the foundation's GPLv2 server, or a separate company's MariaDB Cloud tiers. Compare the first ninety days in staff hours, not just invoices, since an unpatched self-run server is also a cost, and a managed service that is too small to hold your data is a different one.
Count the staff hours for backups, upgrades and monitoring if you self-run
Ask any managed vendor which tier has the SLA and support you need
Price a test workload on the cloud calculator before signing
Licence terms decide who can build on an engine
Database licences differ more than prices do. PostgreSQL uses a permissive licence and its project says it will not change. MongoDB's server is under the SSPL, which obliges anyone offering it as a service to publish their stack. Redis 8 gives a choice of RSALv2, SSPLv1 or AGPLv3, and only AGPLv3 is OSI approved.
CockroachDB moved to its own Software Licence from version 24.3, with a free self-hosted licence for companies under 10 million in revenue. SQLite is public domain. A licence written for the vendor's benefit can matter when you resell the product, embed it in software you ship, or host it for customers, so read it before the architecture is fixed.
Ask legal which of AGPL, SSPL or a vendor licence your product can accept
Check whether the licence changes if you host it for customers
Note any telemetry condition attached to a free licence
Matching the engine to the workload
A wrong fit costs more than any licence. SQLite allows one writer at a time and its own site recommends a client/server engine for busy sites. Apache Cassandra suits high write volumes across data centres, but CQL runs no joins, so tables follow queries. Couchbase and MongoDB store JSON documents, and DynamoDB suits key-based lookups on AWS.
Redis keeps data in RAM and works best beside a primary database. Oracle Database and Microsoft SQL Server cover general enterprise workloads but add licence counting. Write down your top ten queries, with the volume of reads and writes each one makes, and test them on the shortlist rather than on a vendor demo.
List your ten most frequent queries and test each engine on them
Check concurrency: how many processes write at the same moment
Decide whether you need joins, transactions across tables, or neither
Metering, scale limits and the way out
Each engine meters something different. CockroachDB bills per provisioned vCPU-hour, even when idle. Couchbase Capella bills per node-hour, with a three-node minimum for Enterprise. DynamoDB bills request units or provisioned capacity, and an export to S3 does not consume read capacity. SQL Server counts cores, and Standard caps at 32 cores while Express stops at 50 GB.
Oracle publishes a licence price list separately from its cloud rates. For exit, PostgreSQL's pg_dump exports a database consistently and SQLite is a single file. Ask every vendor how the first export works, how long it takes, in what format, and at whose cost, because leaving is only cheap if the data can be read elsewhere.
Model one year of cost at your expected peak, not your launch size
Ask what exports exist, in which format, and whether they are charged
Check the limits of the cheapest tier against your data size
What goes wrong most often when buying database management systems
Choosing a database because it is popular rather than because its query model fits your workload.
Comparing a free licence with a cloud bill and forgetting the staff time that self-running needs.
Reading only the entry price of a cloud tier and missing idle charges, storage multiples and add-on services.
Leaving exit for later, when the data model has already moved into one vendor's own extensions.
07
Frequently asked questions
8 answers
What are the best database management systems in 2026?
PostgreSQL leads our ranking of 12. PostgreSQL is released under a BSD-style licence, and the project says it has no plans to change it, so nobody can reprice the engine.
The cost sits elsewhere: you choose a host or support company from the project's lists. Each major version is supported for five years, and a major upgrade needs a dump and reload or pg_upgrade, which is real planning work.
Which database management systems publish their pricing?
12 of the 12, with the pricing model each one publishes:
PostgreSQL: Free to use under the PostgreSQL Licence; hosting and support bought separately.
MariaDB: Free server under GPLv2; MariaDB Cloud billed per hour, published.
SQLite: Free, public domain; paid support and warranty of title priced on a published list.
CockroachDB: Cloud billed per vCPU-hour, published; self-hosted licence free below a revenue limit.
MongoDB: Free Atlas cluster of 512 MB; Flex and Dedicated billed by the hour, published.
Redis: Free cloud database of 30 MB; Essentials hourly, Pro from a monthly minimum.
Apache Cassandra: Free to run under Apache Licence 2.0; no vendor sells it.
Couchbase: Free Capella cluster; paid Capella tiers per node-hour, published; Server on request.
MySQL: Community Server free under GPLv2; HeatWave metered per ECPU-hour; Enterprise on request.
Microsoft SQL Server: Per core or server plus client licences, list prices published; Express and Developer free.
Oracle Database: Licence price list published as PDF; Oracle Database Free for development within caps.
Amazon DynamoDB: Per request or provisioned capacity, published; monthly free allowance.
The other 0 quote per organisation.
Is there a free database management system?
PostgreSQL, MariaDB, SQLite, MongoDB, Redis, Apache Cassandra, Couchbase offer a free tier or a free self-hosted edition.
Where are these database management system vendors established?
In 2 countries across 2 regions: North America 11, Elsewhere 1.
PostgreSQL: Not stated by the vendor.
MariaDB: United States.
SQLite: United States.
CockroachDB: United States.
MongoDB: United States.
Redis: United States.
Apache Cassandra: United States.
Couchbase: United States.
MySQL: United States.
Microsoft SQL Server: United States.
Oracle Database: United States.
Amazon DynamoDB: United States.
Which database management systems are open source?
Which database management systems can you host yourself?
CockroachDB. The other 11 are hosted by the vendor only.
What should you use instead of PostgreSQL?
MariaDB and SQLite are the next two on this page. MariaDB is for teams moving from MySQL who want GPL terms and foundation governance; SQLite is for Applications, devices and small sites that need storage inside the app.
Who should not buy PostgreSQL?
Buyers wanting one company accountable for support and uptime. Support and hosting must be sourced from third parties, because the project has no single vendor.
If your database management systems product belongs among these 12, tell us what it does and who it is for. Inclusion is an editorial call; what a listing is and is not is set out under software advice.
