The Reddit SWE Interview Guide
See how Reddit runs its software engineer loop, from the recruiter call through the onsite: every round, what each one tests, and what each level pays. Then drill the real questions candidates report from recent loops, so nothing in the room surprises you.
- Loop length: 3 to 5 weeks
- Expected difficulty: Medium
- Signature screen: Tennis-score coding
- Work model: Remote-first
Reddit levels & pay
- Software Engineer (IC3, Entry-Mid)
- Senior Software Engineer (IC4, Senior)
- Staff Software Engineer (IC5, Staff)
- Senior Staff Engineer (IC6, Sr Staff)
- Principal Engineer (IC7, Principal)
The Reddit SWE interview, round by round
Recruiter screen (30 min · call)
The opening conversation. Your recruiter confirms your background, the level you are targeting, your timeline, and your comp expectations, and walks you through how Reddit runs a remote-first loop. It is rarely technical, but it quietly sets your level, and your level shapes how demanding every round after it will be.
- Anchor your level early. Targeting Senior versus Staff changes the difficulty of the whole loop, so be deliberate about where you position yourself.
- Ask about the team's stack and scale. Reddit spans feed, ads, search, and safety, and matching your background to a team helps the recruiter route you well.
- Know your comp range. This is where the negotiation window first opens, and a vague answer here can cap your offer later.
Coding phone screen (45 to 60 min · CoderPad)
One coding problem on a shared editor with a Reddit engineer. The screen is famous for a tennis-scoring question: given a sequence of points won, convert it into the game score at each step, handling love, fifteen, thirty, forty, deuce, advantage, and game. It rewards clean state modeling and careful edge-case handling far more than a clever trick.
- Model the state before you type. Tennis scoring is small but full of special cases, so map deuce and advantage on paper first, then code.
- Narrate as you build. Reddit weights communication heavily, so clarify the rules, state your assumptions, and reason through edge cases out loud.
- Readable beats rushed. Correct, well-named code you can extend for a follow-up outperforms a fragile one-liner you cannot defend.
Onsite coding rounds (2 rounds · virtual)
Two back-to-back coding interviews, each about an hour, on a shared editor over video. The problems lean on practical data structures rather than contest exotica: strings, hash maps, trees, graphs and traversal, intervals, and heaps. Optimal time and space is expected, with edge cases handled before the interviewer has to ask.
- Expect one applied problem. At least one round is framed around a realistic product scenario rather than an abstract puzzle, so tie your approach back to the use case.
- Talk through complexity. State the time and space cost of your approach up front and revisit it when you optimize.
- Test before you declare done. Walk your own code with a small input and a tricky edge case rather than waiting to be corrected.
System design round (60 min · from Senior up)
For Senior candidates and above, one design round on a real Reddit-shaped problem: a home feed, a ranking or recommendation service, comment trees at scale, or a notification fan-out. You will scope requirements, sketch an API and data model, and reason about caching, sharding, and read-heavy fan-out under social-platform traffic, with capacity math you can defend.
- Drive the scoping. Pin down read versus write ratios and consistency needs early, since a feed is read-heavy and that shapes every later decision.
- Go deep on one bottleneck. Depth on ranking freshness, cache invalidation, or fan-out beats a shallow tour that names many technologies.
- Defend your trade-offs. Interviewers push on why you chose a design, so have the alternative and its cost ready.
Behavioral and team fit (45 min · virtual)
A conversation with a hiring manager or senior engineer about how you work: collaboration, ownership, handling ambiguity, and past projects in depth. Because Reddit is remote-first, or digital by default in its own words, interviewers also probe how you communicate and stay aligned without an office, so concrete stories about async work and cross-team influence land well.
- Bring specific stories. Prepare a few STAR examples with real metrics and your exact role, not general statements about how you like to work.
- Show remote-ready habits. Reddit works across time zones, so highlight clear written communication and self-direction.
- Have questions ready. Thoughtful questions about the team's roadmap and how decisions get made read as genuine interest.
How to prepare
Build a daily coding rhythm (Weeks 1 to 4)
Code every day for the month. Rotate through the patterns Reddit leans on, strings, hash maps, trees, graphs and traversal, intervals, and heaps, starting at medium and mixing in the occasional hard, always timed on a shared editor so the format is second nature.
Drill the tennis-score problem and its cousins (Weeks 1 to 2)
Reddit's phone screen famously asks you to convert a run of won points into tennis scores. Solve it cleanly early, then practice similar state-machine problems, parsing, simulation, and running-tally questions, until modeling the special cases feels routine.
Layer in system-design reps (Weeks 2 to 3)
Once your coding is warm, add design if you are targeting Senior or above. Work through three or four Reddit-shaped systems end to end, a home feed, a ranking service, comment trees, and a notification fan-out, saying each decision aloud and preparing for follow-ups on caching and fan-out.
Rehearse stories and run mock loops (Weeks 3 to 4)
Write a handful of STAR stories on ownership, ambiguity, and cross-team work, each with metrics and your role. In the final week, sit a couple of full loops back to back, coding plus design plus behavioral, so your focus holds across several remote interviews in a row.
Recently asked
Tennis game score conversion
About Reddit
Reddit is one of the largest community platforms on the internet, a network of thousands of user-run subreddits where people post, vote, and discuss around shared interests. The product is built on feeds, ranking, comment threads, search, and the safety systems that keep sprawling communities usable at scale, and its engineers work across all of them.
The company is remote-first, describing itself as digital by default, with teams distributed across the United States and hubs in San Francisco, New York, and Seattle. Reddit went public in 2024 and trades as RDDT, and as a newly public company it pairs the reach of an established platform with the pace of a business still building out its ads and data businesses.
Frequently asked
How many rounds is the Reddit interview?
Typically five stages: a recruiter screen, a coding phone screen, two onsite coding rounds, and, for Senior candidates and up, a system-design round, plus a behavioral and team-fit conversation. The whole loop usually runs three to five weeks and is conducted remotely.
What is the famous Reddit tennis question?
Reddit's coding phone screen is well known for a tennis-scoring problem: given the sequence of points each player wins, output the game score at each step using love, fifteen, thirty, forty, deuce, advantage, and game. It is really a state-modeling exercise, and clean handling of deuce and advantage is what separates a pass from a stall.
How hard is the Reddit SWE interview?
Medium overall. Most reported questions sit in the medium band, with a smaller share rating hard, concentrated in graph problems and the system-design round. The coding bar is beatable with steady pattern practice, and communication counts as much as raw speed.
Is Reddit remote-first?
Yes. Reddit calls itself digital by default and hires across the United States, so most interviews are conducted over video and many roles are fully remote. It keeps hubs in San Francisco, New York, and Seattle for people who prefer some in-person time.
What does the Reddit system-design round cover?
For Senior and above, expect a Reddit-shaped problem: a home feed, a ranking or recommendation service, comment trees at scale, or a notification fan-out. You scope requirements, sketch an API and data model, and reason about caching, sharding, and read-heavy fan-out under social-platform traffic.
What coding topics should I focus on?
Practical data structures over contest exotica. Reddit leans on strings, hash maps, trees, graphs and traversal, intervals, and heaps. Optimal time and space is expected, and at least one onsite problem is usually framed around a realistic product scenario.
Does Reddit ask system design for entry-level roles?
Generally no. Entry and early-mid candidates face coding and behavioral rounds without a dedicated design interview. The system-design round enters the loop from the Senior level up, where scope and architecture judgment start to matter.
How is Reddit engineering compensation structured?
Base salary plus RDDT restricted stock units that vest over four years, and often a one-time sign-on in the first year at the earlier levels. As a public company, Reddit's equity has a clear market value, and total pay is competitive with other top platforms.
How long does the Reddit interview process take?
Usually three to five weeks from recruiter screen to decision, depending on scheduling. Because the loop is remote, rounds can sometimes be arranged quickly, though team-match and debrief steps can add time.
What is the Reddit online assessment?
Not every candidate gets one. Some pipelines include a timed, auto-graded coding assessment before the phone screen, while others move straight from the recruiter call to a live coding screen. Treat any assessment as a real round rather than a formality.
How should I prepare for the behavioral round?
Bring specific STAR stories on ownership, handling ambiguity, and cross-team collaboration, each with real metrics and your exact role. Because Reddit is remote-first, examples that show clear written communication and self-direction without an office land especially well.
Does Reddit value communication in coding rounds?
Heavily. Interviewers want you to clarify the problem, state assumptions, narrate your approach, and reason through edge cases out loud. A correct solution delivered in silence scores worse than a clear, well-explained one.
What levels does Reddit hire software engineers at?
The individual-contributor ladder runs from Software Engineer through Senior, Staff, Senior Staff, and Principal. Your target level is set during the recruiter screen and shapes how many design and leadership signals the loop looks for.
Can I reapply to Reddit if I am rejected?
Yes. Most candidates can reapply after a waiting period, typically several months to a year. Use the gap to close the specific gaps that surfaced, whether that is design depth, coding speed, or sharper behavioral stories, and a stronger second loop is very achievable.
Do Reddit interviewers expect a working, optimal solution?
Yes. On coding rounds, aim for a correct and optimal answer with edge cases handled, then be ready to discuss trade-offs and a follow-up extension. Getting to a clean brute force first and then optimizing out loud is a perfectly good path.