Every week I get the same question in my DMs: "What's the best AI tool for technical interviews? Should I use ChatGPT? Cluely? Just GitHub Copilot?"

So I spent two months testing every option on the market in real interview scenarios - fake interviews with friends, real interviews I wasn't preparing for, and edge cases like coding platforms that disable copy-paste. This is the honest, unfiltered breakdown.

TL;DR

For real interview use: Acemode is the only purpose-built tool that's invisible to screen-sharing AND works offline of the browser. ChatGPT alt-tabbing is detectable. Cluely works but costs more. Browser extensions break on full screen share. Skip them.

What you actually need from an interview AI tool

Before evaluating any tool, you need to be clear about what makes one usable in a real interview vs. just usable in practice. Most "best AI tools for interviews" articles miss this completely - they list features without thinking about the actual interview context.

Here are the four non-negotiable requirements I tested every tool against:

  1. Invisibility during screen share. If your interviewer can see the tool, it's worse than not using one - it's a red flag.
  2. Speed. If the AI takes 20 seconds to respond, the silence becomes obvious. You need answers in under 5 seconds.
  3. No suspicious behavior. No alt-tabbing. No mouse movement to a second monitor. No copying-pasting from another window.
  4. Quality of answer. A wrong answer is worse than no answer. The AI needs to handle algorithm questions, system design, behavioral, and SQL - not just LeetCode mediums.

Most tools fail on at least two of these. Some fail on all four. Let's go through them.

1. ChatGPT (or Claude) directly in a browser tab

What it is: The default option. Open ChatGPT in another tab or window, paste the problem, copy the answer.

What works: The AI quality is genuinely excellent. GPT-4o and Claude Sonnet 4.5 will solve almost any LeetCode medium-to-hard in seconds with clean code. For pure problem-solving capability, these are the gold standard.

What breaks:

Verdict: Great for practice, dangerous in real interviews. Use it if you're 100% confident the interview will only share a single tab. Otherwise, look elsewhere.

2. GitHub Copilot

What it is: AI autocomplete inside your IDE. Suggests code as you type.

What works: If the interview is in VS Code or another supported IDE, Copilot can autocomplete entire functions silently. The interviewer doesn't see anything unusual - it just looks like you're a fast typist with great instincts.

What breaks:

Verdict: Great for IDE-based interviews on a relaxed company. Useless for the modern FAANG-style coding platforms. Doesn't solve system design at all.

3. Cluely

What it is: The most well-known invisible AI assistant. Native desktop app that overlays answers on top of your screen.

What works:

What breaks:

Verdict: Solid product, premium pricing, getting too well-known. If money is no object and you want the most polished experience, it works. But underground tools are catching up - and they're cheaper.

4. Browser extensions (Pieces, AlgoMonster Helper, etc.)

What they are: Chrome extensions that overlay AI suggestions on coding platforms.

What breaks (universal):

Verdict: Non-starter for serious use. The architectural mistake - being inside the browser - can't be fixed. Avoid.

5. Acemode

What it is: The newer entrant. Native desktop app for Mac, Windows, and Linux that's invisible to screen capture at the operating system level.

What works:

What breaks:

Verdict: Currently the best price-to-feature ratio for interview-specific AI assistance. Especially if you're interviewing on platforms that block copy-paste.

The honest comparison table

Here's how each option scores on the four requirements that matter:

Tool Invisible Speed No suspicious behavior Answer quality Price
ChatGPT direct$20/mo
GitHub Copilot⚠️⚠️$10/mo
Cluely$20-50/mo
Browser extensions⚠️⚠️⚠️Free-$15/mo
Acemode$29 once

What I'd actually recommend depending on your situation

If you're interviewing at a chill startup that uses VS Code:

GitHub Copilot is enough. The invisibility doesn't matter as much, and the autocomplete is genuinely useful. Combine with a quick ChatGPT consultation for system design questions if needed.

If you're interviewing at FAANG or FAANG-equivalent on a custom platform:

You need real invisibility. Either Cluely or Acemode. They both work. Pick based on price - Acemode's one-time $29 is the obvious choice unless you have a specific Cluely feature you need.

If money is genuinely tight and you only need it for 1-2 interviews:

The free 3-session trial of Acemode is enough. Use it for your hardest interviews and pay if you need more.

If you're risk-averse and worried about ethics:

Use any of these tools only for preparation, not during real interviews. AI-driven practice is genuinely transformative even before you sit down with a real interviewer. We covered the ethics question in detail in this post.

What's actually changing in this space

Three things to watch over the next 6-12 months:

1. AI detection in interviews is becoming a thing. Some companies are starting to use behavioral analytics - typing rhythm, eye-tracking via webcam, answer-pattern analysis. None of these are reliable yet, but they will be eventually. The window for these tools is now.

2. Pricing will collapse. Acemode's $29 one-time is already ~70% cheaper than Cluely. As more underground tools enter the market, expect to see free options with paid upgrades. The category is racing to zero.

3. Quality will increasingly converge. Every tool eventually uses the same underlying models (GPT-4o, Claude, Gemini). The differentiator becomes how it's packaged - invisibility, speed, format of answers, resume integration. Not the AI itself.

The uncomfortable truth nobody talks about

The best AI interview tool is the one you don't end up needing because you've prepared properly. AI tools are a safety net for moments when your prep falls short - not a replacement for prep.

Use them. They work. But also do the LeetCode practice. Read the system design primer. Practice behavioral answers out loud. The combination of preparation plus a safety net is unbeatable.

Walking into an interview having prepared seriously, with Acemode as your insurance for the hard moments - that's the actual winning configuration. Not relying on the tool to do all the work.