Design Google Maps
PremiumProduct architectureHard
- Vector map tiles
- Route planning
- Contraction hierarchies
Quick answer
This product architecture interview question asks you to design Google Maps. Aim for a design that meets its requirements at the stated scale, then explain its main components, data flow and trade-offs. Interviewers want to see how you scope the problem, size it and defend each choice.
The problem
Design Google Maps, a map and navigation app that draws the map at any zoom, finds a driving route using live traffic and guides drivers turn by turn. The hard parts are answering route queries on a world-sized road graph in milliseconds and turning millions of phone GPS readings into live traffic speeds.
What must the system do?
- Map view: The map draws at zoom levels 0 to 18 with road names, and pans and zooms smoothly on phone and web.
- Route: For a start and a destination, return the fastest driving route and up to 2 alternatives, each with distance and an ETA using current traffic.
How well must it do it?
- Fast routes: A route query of up to 1,000 km returns in under 300 ms at p99.
- Smooth map: Tiles for a new screen load in under 500 ms on 4G, mostly from the phone cache and the CDN.
What scale should you design for?
Use these numbers in your estimates.
The scale numbers unlock with this questionUnlock
Key concepts
- Vector map tiles
- Route planning
- Contraction hierarchies
- Live traffic
- Navigation rerouting
- Map matching
How you’ll practise
- Requirements
- Core entities
- API design
- Client and server flow
- Scale and edge cases
- Wrap-up
Lala, personalized to you, gives a hint when you ask and reviews your design when you are ready.
What do interviewers look for?
In any product architecture design round.
- Clarifies the requirements before drawing anything
- Uses a few numbers that actually change the design
- Draws a clear path from the client to storage
- Picks storage and caching with reasons, not by habit
- Explains what breaks first under load and how to fix it
- States trade-offs openly instead of claiming a perfect design
Questions people ask about this interview question
- Which design type is this question?
- It is a product architecture question. You design Google Maps and explain your choices the way you would in an interview.
- Is this question asked at entry level?
- It is marked Hard. It suits engineers preparing for senior interviews, where you are expected to drive the discussion and go deep on trade-offs.
- What should I cover first?
- Start with the requirements: what the system must do, how well it must do it and which numbers change the design. Agree on scope with the interviewer before you design anything.
- Can I practise it for free?
- It is a premium question. Sign up and unlock it once for 10 credits; it then stays unlocked. When you finish, Lala, your personalized AI mentor, can review your design for 30 credits.
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Updated · Written by the SevyDevy team