Cloudflare Workers KV
activeby Cloudflare · since 2018 · also known as Workers KV, Cloudflare KV
Globally cached, eventually consistent key-value store for read-heavy data at Cloudflare's edge.
Overview
Workers KV is Cloudflare's global key-value store for Workers: values are written to central storage and cached in data centers close to readers, so hot keys come back in milliseconds anywhere in the world. The trade-off is eventual consistency, since a write can take up to about 60 seconds to be visible in other locations, and per-key write rates are limited (about one write per second per key). That makes it ideal for configuration, feature flags, redirects, static assets and auth tokens that are read far more than written. For counters, coordination or anything needing read-after-write consistency, Cloudflare points you to Durable Objects or D1.
Strengths & trade-offs
Strengths
- +Low-latency reads worldwide via Cloudflare's edge cache
- +Zero configuration from Workers: bind a namespace and call get/put
- +Generous free tier and no egress charges
- +Per-key expiration (TTL) and metadata
- +Values up to 25 MiB, suitable for small assets
Trade-offs
- −Eventually consistent: writes take up to about 60 seconds to propagate
- −Roughly one write per second per key
- −No transactions, queries or secondary indexes; list is prefix-only
- −Cache misses for cold keys are noticeably slower
Great for
- +Feature flags and configuration at the edge
- +URL redirects and routing tables
- +Authentication tokens and API key lookups
- +Caching rendered pages or API responses
- +Static asset storage for Workers apps
Think twice for
- −Counters or frequently updated keys
- −Read-after-write consistency
- −Relational or queryable data
Capabilities
Native or official first-party support · 4 of 25 tracked
Scale & consistency
- Comfortable data size
- Large · ≤ 1 PB
- Horizontal scaling
- Native
- Multi-region
- Read replicas
- Transactions
- None
- Consistency
- Eventual
- Schema
- Schemaless
- Architecture
- Distributed, Serverless
- Query languages
- Workers KV API
Reads served from edge caches in hundreds of cities; writes go to central stores and propagate within about 60 seconds.
Deployment
available on · Cloudflare
Ecosystem
Alternatives to Cloudflare Workers KV
Single-threaded stateful actors at the edge, each with its own strongly consistent SQLite store.
cloudflare-workers-kv vs cloudflare-durable-objects →Vercel's globally replicated read-optimized config store (renamed Global Config in 2026).
cloudflare-workers-kv vs vercel-edge-config →Key-value store built into the Deno runtime; its hosted backend ends with Deno Deploy in 2027.
cloudflare-workers-kv vs deno-kv →Serverless SQLite for Cloudflare Workers, priced per row read and written, with read replicas and time travel.
cloudflare-workers-kv vs cloudflare-d1 →Serverless, per-request-priced Redis with an HTTP API built for edge and serverless functions.
cloudflare-workers-kv vs upstash →AWS's serverless key-value and document store with single-digit-millisecond reads at any scale.
cloudflare-workers-kv vs amazon-dynamodb →Cloudflare Workers KV FAQ
What is Cloudflare Workers KV?
Cloudflare Workers KV is a key-value database by Cloudflare, first released in 2018. Workers KV is Cloudflare's global key-value store for Workers: values are written to central storage and cached in data centers close to readers, so hot keys come back in milliseconds anywhere in the world. The trade-off is eventual consistency, since a write can take up to about 60 seconds to be visible in other locations, and per-key write rates are limited (about one write per second per key). That makes it ideal for configuration, feature flags, redirects, static assets and auth tokens that are read far more than written. For counters, coordination or anything needing read-after-write consistency, Cloudflare points you to Durable Objects or D1.
Is Cloudflare Workers KV open source?
No. Cloudflare Workers KV is proprietary, closed-source software.
Does Cloudflare Workers KV support ACID transactions?
No. Cloudflare Workers KV does not provide ACID transactions; its consistency model is eventual.
Does Cloudflare Workers KV scale horizontally?
Cloudflare Workers KV scales horizontally out of the box, with built-in sharding or partitioning. It is comfortable at large scale (≤ 1 PB). It supports cross-region read replicas.
How can I run Cloudflare Workers KV?
You can use the vendor's managed cloud, run it serverless and run it at the edge. Managed offerings include Workers KV. It is available on Cloudflare.
What is Cloudflare Workers KV best for?
Cloudflare Workers KV is a strong fit for feature flags and configuration at the edge; URL redirects and routing tables; and authentication tokens and API key lookups. Think twice for counters or frequently updated keys.
What are the best alternatives to Cloudflare Workers KV?
Common alternatives to Cloudflare Workers KV include Cloudflare Durable Objects, Vercel Edge Config, Deno KV, Cloudflare D1 and Upstash. The right choice depends on your workload, scale and hosting; WhichDB's smart match ranks them against your requirements.
How popular is Cloudflare Workers KV?
Cloudflare Workers KV ranks #404 of 844 databases on the WhichDB Score (4.4/100), and #59 among key-value databases. The score combines public adoption signals such as package downloads, GitHub activity, job posts and developer discussion.