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Top 50 Redis Interview Questions & Answers (2026)

50 Questions 20 Beginner 20 Intermediate 10 Advanced

About Redis

Top 50 Redis interview questions covering data structures, caching, persistence, clustering, and real-world use cases. Companies hiring for Redis roles test this knowledge at every stage — from first-round screens that check the basics to final-round conversations about real-world trade-offs.

What to Expect in a Redis Interview

Expect a mix of conceptual and practical Redis questions: clear definitions and core-concept checks for junior roles, hands-on scenario questions for mid-level roles, and architecture or trade-off discussions for senior roles. Interviewers usually move from foundational topics toward the kind of problems you'd actually face on the job.

How to Use This Guide

Work through the Redis questions in order — Beginner, then Intermediate, then Advanced — so each concept builds on the last. Every question has its own page; bookmark the ones that trip you up and revisit them the day before your interview.

Curated by Tech Baithak Editorial Team · Last updated: May 2026

Beginner 20 questions

Core concepts every Redis developer must know.

01 What is Redis? 02 How is Redis different from a traditional disk-based database? 03 What are the five core Redis data types? 04 What do the SET and GET commands do in Redis? 05 How does TTL (Time-To-Live) work in Redis? 06 What is the difference between Redis and Memcached? 07 What are the Redis persistence options (RDB and AOF)? 08 What is Redis Pub/Sub? 09 What are common real-world use cases for Redis? 10 What is Redis pipelining? 11 What does it mean that Redis operations are atomic? 12 What are the INCR and DECR commands in Redis? 13 What are LPUSH, RPUSH, LPOP, and RPOP in Redis? 14 What are SADD and SMEMBERS in Redis? 15 What are ZADD and ZRANGE in Redis? 16 What are HSET and HGET in Redis? 17 What are Redis SELECT databases? 18 How does Redis AUTH work? 19 What does FLUSHDB do in Redis? 20 What does the Redis INFO command return?

Intermediate 20 questions

Practical knowledge for developers with hands-on experience.

01 What is Redis Cluster and how does it shard data? 02 What is the difference between Redis Sentinel and Redis Cluster? 03 How do MULTI and EXEC work in Redis transactions? 04 What is WATCH and optimistic locking in Redis? 05 What is Lua scripting in Redis and when should you use it? 06 What are Redis eviction policies? 07 What is HyperLogLog in Redis? 08 What are Redis Streams? 09 What are Redis Geospatial commands? 10 What is RedisBloom (Bloom Filter in Redis)? 11 How do you implement rate limiting in Redis? 12 How does distributed locking work in Redis? 13 What is the cache-aside pattern vs write-through caching? 14 How does Redis replication work? 15 What is the Redis slow log? 16 What is OBJECT ENCODING in Redis? 17 What are Redis keyspace notifications? 18 What are CLIENT commands in Redis? 19 What is CLIENT TRACKING in Redis (client-side caching)? 20 How do you work around cross-slot transaction limitations in Redis Cluster?

Advanced 10 questions

Deep expertise questions for senior and lead roles.

01 How does Redis Cluster sharding and the hash slot algorithm work in detail? 02 What is consistent hashing and how does it compare to Redis Cluster's approach? 03 What is memory optimization in Redis (ziplist, listpack, and encoding thresholds)? 04 How does AOF rewrite work and how does it compare to RDB performance? 05 What are Redis Functions (replacing Lua scripts in Redis 7+)? 06 What is Redis Stack and what does it add to vanilla Redis? 07 What are large key anti-patterns in Redis and how do you fix them? 08 What is CRDT support in Redis and how does it relate to Active-Active geo-distribution? 09 How do you optimize Redis memory usage for a large-scale deployment? 10 How does Redis handle high availability in production and what are the failure modes to understand?

Back to All Topics 50 questions total