Cloudant vs PlanetScale

What Cloudant is

IBM Cloudant is a proprietary managed JSON document database built on Apache CouchDB, with a compatible HTTPS API and replication protocol. The Lite plan is free for evaluation and fixes capacity at 20 reads, 10 writes and five global queries per second with 1 GB storage. Standard begins at one provisioned capacity block—100 reads, 50 writes and five global queries per second—includes 20 GB and bills capacity plus excess storage hourly. Dedicated Hardware adds workload isolation, private networking and selected compliance and key-management options. A Cloudant service is not the same as self-hosting CouchDB.

What PlanetScale is

PlanetScale is a managed MySQL platform whose distinguishing feature is database branching: you branch a schema like code, open a deploy request, and merge it without locking tables. Schema changes stop being the scary part of a release: a branch is reviewed and merged without locking the table. The trade-off is that foreign key behaviour and some MySQL features work differently under its sharding model, which has to be designed for.

What Cloudant is built to do

JSON document database

Stores schema-flexible documents, attachments and secondary indexes behind HTTPS APIs.

CouchDB-compatible replication

Supports replication patterns between Cloudant regions and compatible CouchDB systems.

Provisioned throughput

Scales read, write and global-query capacity in linked blocks through the dashboard or API.

IBM IAM and SDKs

Integrates IBM Cloud access controls and provides supported Java, Node.js, Python, Swift, Go and mobile clients.

What PlanetScale is built to do

Database branching

Branches a schema like code and merges it through a deploy request.

Non-blocking schema changes

Applies migrations without locking tables in production.

Managed MySQL

Runs MySQL-compatible clusters without server administration.

Choose Cloudant if

• Offline or distributed applications that benefit from CouchDB-style replication
• JSON workloads dominated by key lookups and well-designed partitioned queries
• Teams able to test request-class capacity, 429 handling and multi-region conflicts

Skip Cloudant if

• The application depends on relational joins, broad ad-hoc SQL or multi-document ACID transactions
• Traffic is too unpredictable to provision and monitor request-class capacity
• A free Lite instance is being treated as a production SLA or scalable datastore

Choose PlanetScale if

• Teams that want managed Postgres or Vitess MySQL with 3-node high availability from $15/month
• Dev and staging databases on single-node Postgres from $5/month
• Workloads that need local NVMe performance: Metal Postgres from $50/month with 10 GiB

Skip PlanetScale if

• You expect a free tier — none is listed on the pricing page
• You run Vitess Metal for a small app: it starts at $609/month
• Your cloud region is not us-east-1; prices vary by provider and region

Cloudant: pros & cons

• Managed document service: IBM handles database servers, upgrades, patching and core high-availability infrastructure.
• CouchDB lineage: Compatible HTTP APIs and replication ease selected CouchDB application and migration patterns.
• Explicit capacity model: Read, write and global-query throughput are provisioned in documented blocks.
• Multi-region option: Application-managed replication can support active-active regional architectures.
• Lite is evaluation capacity: It cannot scale and blocks new writes above its storage limit.
• Capacity dimensions scale together: A workload dominated by one request class may pay for unused allowances in the others.
• Exceeding throughput returns 429: Applications need retry, backoff and load testing rather than assuming automatic unlimited scale.
• Cross-region is not automatic application resilience: Conflict behavior, traffic routing, monitoring and recovery remain design responsibilities.

PlanetScale: pros & cons

• Schema changes without downtime
• Branching workflow that mirrors Git
• Managed, with no server maintenance
• No foreign key constraints in the traditional sense
• Costs rise quickly beyond small workloads
• Ties you to their platform and workflow