Introduction
TikTok OA (Online Assessment) is a crucial step in the company’s technical hiring pipeline. Whether you’re applying for a software engineer or data-related role, the OA is designed to filter candidates based on problem-solving skills, programming ability, and overall technical readiness.
In this blog, we will share real insights from a May 2025 TikTok OA, common question patterns, and actionable tips to help you prepare efficiently and avoid common pitfalls.
TikTok OA Overview
The TikTok OA generally includes the following components:
- Two Algorithmic Coding Problems: Usually medium to hard difficulty, based on data structures, algorithms, or optimization.
- Work Simulation/Behavioral Section(for some roles): Evaluates your decision-making and alignment with TikTok’s values.
- Technical Multiple Choice Questions: For certain positions, expect 8–10 MCQs on system design, networking, OS, or SQL.
You’ll typically have 70–90 minutes to complete the entire assessment, depending on the role and location.
Real Question From May 2025 OA
One widely discussed question from the May 2025 TikTok OA is as follows:
“Binary Array – Minimum Transition” Problem
Prompt (paraphrased):
You are given a binary array containing 0s (standard videos) and 1s (priority videos). Your goal is to rearrange the array with the minimum number of swaps to reduce transitions between 0s and 1s — i.e., to group similar elements together and minimize switching.
Example:
Input: [1, 0, 1, 0, 1, 0]
Output: 2 (minimum 2 swaps needed to group all 1s together)
Solution Idea:
Use a sliding window approach. Count how many 1s there are, and then find the subarray of that size with the maximum number of 1s already in place — the remaining are the ones you’d need to swap. This is similar to classic problems like “minimum swaps to group all 1s together”.
Code Strategy
Time complexity: O(n)
Space complexity: O(1)
Common TikTok OA Patterns
From various shared experiences (source at ProgramHelp), TikTok seems to favor these patterns:
- Sliding Window and Prefix Sums
- Greedy + Sorting
- DFS/BFS on grids or graphs
- String processing (like parentheses validation or substring matching)
- Bit manipulation(occasionally)
Top Tips to Pass TikTok OA
1. Master Pattern-Based Coding
Focus on solving category-based problems: sliding window, two pointers, binary search, etc. LeetCode problems tagged “TikTok” or “OA” are great for practice.
2. Time Management
Don’t get stuck on one hard problem. Prioritize finishing one full problem and partially solving the second if needed.
3. Simulate the Real Environment
Use platforms like HackerRank, CodeSignal, or CodeStudio to simulate OA environments, including timed practice sessions.
4. Review Past Questions
Sites like ProgramHelp.net, LeetCode Discuss, and 1point3acres have candidate-submitted TikTok OA questions. Reviewing them gives you real insight into the company’s style.
5. Avoid Shortcuts or Plagiarism
Some candidates attempt to use cheating tools during the OA. As ProgramHelp warns, TikTok uses strict detection systems (like video monitoring, tab tracking, and code similarity checks). Cheating may result in disqualification from all Bytedance positions for life.
Conclusion
TikTok OA is challenging but highly predictable if you’ve practiced the right patterns and stayed disciplined. In particular, knowing sliding window techniques, greedy algorithms, and a few tricky edge cases can significantly improve your chances.
Lastly, integrity matters. Stay sharp, practice smart, and go into the assessment prepared — not just technically, but ethically too.