OpenAI
Hard
Software EngineerDesign a distributed crossword solving service
System Design
18
0
October 17, 2025
Load Balancing Interview Questions
Load balancing questions test your understanding of how to distribute traffic across multiple servers effectively.
Expect discussions on algorithms (round-robin, least connections, consistent hashing), health checks, and failover strategies.
Interviewers evaluate whether you understand when and why to use different load balancing approaches.
395Questions
100Companies
Easy 17 • Medium 133 • Hard 242Difficulty mix
Common load balancing interview patterns
- Round-robin vs least-connections vs consistent hashing
- Layer 4 (TCP) vs Layer 7 (HTTP) load balancing
- Health checks and automatic failover
- Session affinity and sticky sessions
- Global server load balancing (GSLB) for multi-region
- Load balancer as a single point of failure and redundancy
Load balancing interview questions
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OpenAI
Hard
Software EngineerDesign reliable high-volume chatbot system
System Design
22
0
December 6, 2025
DoorDash
Hard
Software EngineerDesign review system with voting and rewards
System Design
17
0
September 6, 2025
DoorDash
Hard
Software EngineerDeep-dive a project architecture
System Design
13
0
July 31, 2025
Brex
Hard
Software EngineerDesign Points-from-Transactions Service
System Design
22
0
August 14, 2025
Box
Hard
Software EngineerImplement a leaky-bucket rate limiter
System Design
22
0
August 1, 2025
Anthropic
Hard
Software EngineerDesign a scalable, reliable system
System Design
17
0
September 6, 2025
OpenAI
Medium
Software EngineerDesign a scalable payment system
System Design
23
0
February 2, 2026
Chime
Easy
Software EngineerDesign load balancing, caching, and idempotent APIs
System Design
18
0
November 13, 2025
Optiver
Hard
Software EngineerDesign a subscription push service
System Design
21
0
July 17, 2025
Roblox
Hard
Software EngineerDesign real-time game matchmaking service
System Design
20
0
September 6, 2025
Snowflake
Easy
Software EngineerDesign a disk-backed KV store under contention
System Design
22
0
March 1, 2026
Rippling
Medium
Software EngineerDesign a user behavior monitoring system
System Design
15
1
December 4, 2025
Airbnb
Medium
Software EngineerDesign a scalable notification system
System Design
14
0
November 20, 2025
Instacart
Hard
Software EngineerDesign scalable inventory system and avoid races
System Design
16
0
September 6, 2025
Confluent
Hard
Software EngineerDesign a distributed key-value store at scale
System Design
15
0
July 26, 2025
Rippling
Hard
Software EngineerDesign a news feed aggregator
System Design
9
0
July 26, 2025
OpenAI
Hard
Software EngineerDesign an in-memory database
System Design
11
0
August 4, 2025
StubHub
Medium
Software EngineerDesign Event Email System
System Design
18
0
August 4, 2025
Booking.com
Medium
Software EngineerCompare heap, stack, Protobuf, gRPC, SQL, CI/CD
System Design
24
0
July 29, 2025
Common mistakes with load balancing
- Forgetting that the load balancer itself can be a bottleneck
- Using sticky sessions when stateless design is possible
- Not considering health check latency and false positives
- Ignoring the difference between L4 and L7 load balancing
How load balancing questions are evaluated
Demonstrate understanding of trade-offs between different algorithms.
Explain how the system handles server failures gracefully.
Consider the load balancer in the context of the overall system architecture.