Exponent vs Hello Interview (2026): Which Is Better for System Design?

Exponent, now trading as Aced, is a subscription ($79 a month or $149 a year as of October 2026) with courses for PM, TPM, data and engineering roles plus live peer mock interviews. Hello Interview is a system design course for software engineers with a free core and one-time Premium from $47 (also October 2026). For system design, buy Hello Interview; for non-SWE roles or human practice partners, buy Exponent. PracHub, which also sells interview prep, publishes this comparison.

Pricing and product details were checked on October 14, 2026.

Quick Verdict

Choose Exponent (Aced) when you are interviewing for PM, TPM, data science or another non-SWE track, or you want scheduled practice against live peers. Its free Basic tier includes 5 peer mocks a month.

Choose Hello Interview when you are a software engineer whose weak round is system design or low-level design, and you would rather pay once than subscribe.

If you want to start free, read Hello Interview's free System Design in a Hurry course for the syllabus, then work real system design questions for your target company on PracHub, where most questions are free.

Exponent and Hello Interview at a Glance

What Exponent Offers

Exponent rebranded to Aced: tryexponent.com now redirects to aced.io and the old pricing and FAQ paths return 404. The site does not say when this happened.

As of October 2026 it sells a membership built around video courses for about twenty tracks, from Product Management and System Design to Investment Banking and Security Engineer, plus unlimited peer mock interviews, a members-only Discord, priority job referrals and a question bank of 5,386 user-contributed questions. Pro costs $79 a month or $149 a year. The Expert tier ($99 a month or $249 a year) is the only one with the AI mock interviews, AI feedback and the "Chat with Ace" coach. Coaching is separate at $249 per 60-minute session and does not include membership.

The free Basic tier gives sample lessons, 5 peer mocks a month and limited access to the question database, with no solutions. The main drawback: candidates report on Blind that paying added few videos beyond Exponent's free YouTube content and that its answers were thin. Those threads date from 2020 to 2022, before the AI features and the rebrand. Our Exponent review covers the course model in more depth.

What Hello Interview Offers

Hello Interview is engineer-first. Its free material is the draw: System Design in a Hurry, an ML system design track and company guides that cover Meta, Amazon, Google, OpenAI, Anthropic, Airbnb and Microsoft by level.

Premium is a one-time purchase. When checked on October 14, 2026, it cost $47 for a month, $95 for a year or $319 for lifetime access, each after an auto-applied 20% discount on list prices of $59, $119 and $399. Neither the monthly nor the yearly pass renews. Premium adds the behavioral and concurrency courses, an AI tutor, a crowd-sourced question library and Guided Practice: 34 system design problems, 8 low-level design problems, 12 AI-enabled coding problems and a behavioral track. Its premium page counts about 65 articles and 29 videos across all of Premium, and those counters move.

What changed: Hello Interview ended 1:1 human mock interviews and mentorship on May 31, 2026, so practice there is AI-only. The drawbacks: no free trial, refunds only at the company's discretion, and a Blind thread from October 2025 asking whether the per-level bar on its practice problems is too lenient.

Head to Head

System design depth

Hello Interview wins. It publishes what you get (34 guided system design problems and 8 LLD problems as of October 2026) and gives away its core syllabus. Exponent sells a System Design course too, but its course catalog loads in the browser and showed no lesson or video counts when we checked on October 14, 2026. Its courses include free lessons, so sample one before paying. For a senior or staff software engineering loop, Hello Interview is the more focused product.

Practice format

This is now the clearest split. Only Exponent still puts you in front of other humans: peer mocks on a schedule across PM, DSA, system design, behavioral, SQL and data science, plus paid 1:1 coaching. Hello Interview's is AI Guided Practice on a whiteboard, with step-by-step prompts and feedback. If you freeze when a real person interrupts, AI prompts are a weak substitute; if you want reps at 2 a.m. without booking anyone, they fit. Exponent's own AI interviewer sits on the Expert tier, so it costs $99 a month, not $79. We list other ways to get human reps in HelloInterview Mock Interviews Are Gone.

Price and billing

Hello Interview costs less at either length, as of October 2026. One month is $47 against $79 for Exponent Pro, which auto-renews until you cancel from your account page. An eight-week search needs Hello Interview's $95 year, against $149 for Exponent's annual plan or $158 for two Exponent months. Over a full year the gap is $54. Buy the length you need up front: Hello Interview's FAQ warns that a month and then an upgrade costs more than the year.

Refunds and terms

Cheaper is not lower risk. Exponent refunds a membership in full within 5 days. Hello Interview calls its fees non-refundable and considers refunds case by case, only for users who have not consumed the content. Both require binding arbitration and waive class actions (Hello Interview's unless you opt out). Hello Interview's terms also say its AI features send your responses to third-party AI providers, including OpenAI, Anthropic and Google, and that lifetime access depends on Premium continuing to exist.

Audience

Exponent covers far more roles. A PM, TPM, product designer or solutions architect gets no course built for their role at Hello Interview. A backend engineer pays for an Exponent catalog that is mostly for someone else.

Who Should Pick Exponent

Pick Exponent (Aced) when you are interviewing outside software engineering, where structured video courses are harder to find. It also wins when you want live peer mocks on a schedule, one vendor for courses, coaching, resume review and negotiation, or one annual plan ($149 as of October 2026) across several role types. Cancel inside the 5-day refund window if the courses repeat what you know.

Who Should Pick Hello Interview

Pick Hello Interview when your gap is senior or staff system design, or low-level design, at a large tech company and you want a syllabus you can read free before paying. It also wins for guided whiteboard practice with per-step AI feedback, a level-specific guide for Meta E5, Amazon L6 or a Google manager role, or a purchase with no renewal. Read the free course first, because a refund is not guaranteed.

The Third Option: PracHub

Both products sell a method; their question banks are the weak part. Exponent's 5,386 questions are user-contributed and its free tier shows no solutions. Hello Interview's library is crowd-sourced, comes with Premium, and its own pages size it anywhere from 5,000+ to 13,000+ (both October 2026). PracHub is built the other way round: a bank of real, recently asked interview questions with in-depth written solutions. As of October 2026 it lists more than 12,000 questions from more than 550 companies, including more than 1,500 system design questions; more than 7,000 have a written solution, and most questions are free. It is free to start with an optional paid tier (see pricing). If Hello Interview is the one you were weighing, this page covers when PracHub alone is enough.

Asked at OpenAI: Design a real-time trivia battle royale platform with live spectating Players fill a room, each round knocks out the wrong and the slowest answers, and spectators follow any live room's leaderboard. You design matchmaking, the round loop and the spectator feed.

Asked at Google: Design LLM summarization of e-commerce reviews with prompt-injection and PII defenses A pipeline feeds customer reviews to an LLM that writes summaries for an internal dashboard, and the interviewer spent the time on untrusted input: prompt injection, sanitization and personal data.

A workflow that uses all three:

1. Learn the system design syllabus from Hello Interview's free course.
2. Answer three real prompts cold from PracHub's system design questions for your target company, about 35 minutes each, the length Hello Interview gives its guided problems.
3. Pay for Hello Interview Premium or an Exponent month only for the gap those answers expose: stalling mid-design points to Guided Practice, freezing in front of a person to peer mocks.

Practice these on PracHub

System design prompts from recent loops, plus behavioral, the other round both products teach. The prompts are free to read.

System design (Design a Parallel and Resumable Model Downloader at Anthropic · Design a Real-Time Multi-Source Change Data Pipeline at Autodesk); more in the system design questions.

Behavioral (How You Use AI Tools at AMD · End-to-End ML Project Deep Dive at Figma); more in the behavioral questions.

Browse by role on the software engineer questions, or open all interview questions by company and round.

Frequently Asked Questions

Is Exponent or Hello Interview better for system design?

Hello Interview, for software engineers. As of October 2026 it has 34 guided system design problems, 8 low-level design problems and a free System Design in a Hurry course. Exponent (now Aced) also sells a System Design course, but its catalog showed no lesson or video counts when we checked on October 14, 2026. Exponent is the better pick only if you also need PM, TPM or data tracks, or want live peer mocks.

Which is cheaper, Exponent or Hello Interview?

Hello Interview, at either length. As of October 2026 a month of Premium is $47 against $79 for Exponent Pro, and a year is $95 against $149. Exponent's annual plan costs $54 more and is worth it only if you need its non-SWE courses or peer mocks. Exponent auto-renews but refunds in full within 5 days; Hello Interview does not renew and its fees are non-refundable.

Does Hello Interview still offer mock interviews?

Not with humans. Hello Interview ended 1:1 human mock interviews and mentorship on May 31, 2026, and its refund window for unused mock credits has closed. Practice there is now AI Guided Practice. Exponent still runs peer mock interviews, with 5 a month on its free Basic tier, and sells 1:1 coaching at $249 per 60-minute session as of October 2026.

Is Hello Interview Premium worth it?

Yes if system design or low-level design is your weak round and you will use the guided practice. Read the free System Design in a Hurry course first, because Premium has no free trial and its terms call the fees non-refundable, with refunds only at the company's discretion. If your gap is product sense or analytics, it is the wrong product.

Is there a free alternative to Exponent and Hello Interview?

PracHub is free to start with an optional paid tier. As of October 2026 it lists more than 12,000 real interview questions from more than 550 companies, including more than 1,500 system design questions, and most questions are free. It is a question bank with written solutions, not a course, so pair it with Hello Interview's free system design course if you need a syllabus.

Can I use both Exponent and Hello Interview?

Yes: Hello Interview for the system design syllabus and AI guided practice, Exponent for live peer mocks or a PM or TPM course. Buy one at a time, because Exponent's 5-day refund window and Hello Interview's discretionary refunds leave little room to undo a purchase you do not use.

Final Verdict

For a software engineer whose problem is system design, Hello Interview is the better buy in October 2026. The free course is the better starting syllabus of the two, the guided problem counts are public, and Premium costs less than Exponent at either length: $47 against $79 for a month, $95 against $149 for a year. Accept that refunds are discretionary and that practice is now AI-only.

For everyone else, Exponent (Aced) wins on breadth: PM, TPM, data and design tracks, and live peer mocks Hello Interview no longer offers. Older complaints say its answers are thin, so use the 5-day refund window to check.

Whichever you buy, test yourself on real, recently asked questions. Start with PracHub's question bank, where most questions are free.