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Web Development · head to head

Preact vs Redis

Preact logo

Preact

Web Development

3kB alternative to React with the same modern API

From
Free
Rated
-
Full reviewWebsite
Redis logo

Redis

Technology

The real-time data platform

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Preact compatibility through preact/compat is good but not total, and some React libraries break in ways that are hard to diagnose; Redis licensing changed from BSD to AGPL in 2025, impacting open-source usage
  • They diverge on capability: Preact covers 3kB runtime, Redis covers In-memory data store.
  • Prices and features above were last checked on 30 August 2026.

Where they differ

Only the attributes on which Preact and Redis actually diverge.

Attributes where Preact and Redis differ
AttributePreactRedis
Pricing modelOpen source, no licence feeUnknown
PlatformsWebLinux, macOS, Windows
CategoryWeb DevelopmentTechnology
FoundedUnknown2009

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

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 Preact

  • 3kB runtime
  • preact/compat
  • Same modern API
  • Fast rendering

Only in Redis

  • In-memory data store
  • Data structures
  • Pub/Sub messaging
  • Lua scripting
  • Transactions
  • Persistence options
  • Replication
  • Clustering

What people use each for

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

Preact

  • Embedded widgets that load inside someone else’s page and must stay smallnot Redis
  • Marketing and content sites where JavaScript payload affects Core Web Vitalsnot Redis
  • Applications targeting low-bandwidth or low-powered devicesnot Redis

Redis

  • Cachingnot Preact
  • Session managementnot Preact
  • Real-time analyticsnot Preact
  • Message queuingnot Preact
  • Leaderboardsnot Preact

Where each one falls short

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

Preact

  • Compatibility through preact/compat is good but not total, and some React libraries break in ways that are hard to diagnose
  • Behavioural differences from React exist in edge cases, particularly around event handling
  • A much smaller community, so unusual problems have fewer existing answers than React

Redis

  • Licensing changed from BSD to AGPL in 2025, impacting open-source usage
  • All data must fit in memory, limiting scalability to available RAM
  • No built-in support for multi-tenancy
  • Limited transaction support compared to traditional databases

Pricing, plan by plan

Preact

Free
  • PreactFree
    • Full library
    • Commercial use permitted
    • No usage limits

Redis

Free

No published plan breakdown. See the Redis review.

Which should you pick?

Choose Preact if

  • You need 3kb runtime.
  • You want to start without paying.
  • You also want preact/compat.
Preact review

Choose Redis if

  • You need in-memory data store.
  • You want to start without paying.
  • You work on Linux, macOS, Windows.
  • You also want data structures.
Redis review

Questions people ask

Is Preact or Redis better?
Neither clearly leads. Preact starts at Free and Redis at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Preact or Redis?
Preact starts at Free and Redis at Free.
Does Preact or Redis run on more platforms?
Preact runs on Web. Redis runs on Linux, macOS, Windows.
Can I use Preact for free?
Both have a free tier, so you can try either at no cost before committing.
What is Preact best used for?
Preact is most often used for embedded widgets that load inside someone else’s page and must stay small, marketing and content sites where javascript payload affects core web vitals, applications targeting low-bandwidth or low-powered devices. Of those, embedded widgets that load inside someone else’s page and must stay small and marketing and content sites where javascript payload affects core web vitals are not what Redis is typically brought in for.
What can Preact do that Redis cannot?
Preact covers 3kB runtime, preact/compat, Same modern API, Fast rendering. Redis covers In-memory data store, Data structures, Pub/Sub messaging, Lua scripting.

Answered from the vendors’ own pages

Preact: Is Preact free?

Yes, open source under the MIT licence.

Redis: Is Redis open source?

Redis was open source under the BSD license since its inception in 2009 and has remained open source. However, in 2024-2025, Redis Labs changed licensing to source-available and AGPL, prompting the creation of Valkey, a BSD-licensed open-source fork.

Source
Preact: Can I use React libraries with Preact?

Most, through the preact/compat layer. Compatibility is good but not complete, so libraries relying on React internals can break.

Redis: What is Redis used for?

Redis is an in-memory data structure store used primarily as a cache, database, and message broker. It provides high-speed data access for real-time applications, sessions, leaderboards, real-time analytics, and other use cases requiring fast data retrieval.

Source
Preact: Why choose Preact over React?

Bundle size, almost always. If payload is not a binding constraint, React’s ecosystem is usually the better trade.

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