Quick Answer
Hello Interview is the stronger choice for learning system design and coding content on your own. Mockly is the better choice when your English, not your technical knowledge, is what holds you back, because a UK engineer coaches you live, 1:1, on how you say your answers.
⚡ Quick Stats
- Hello Interview is a self-study platform for software engineering interviews: written breakdowns, videos, Guided Practice problems and an AI mock interviewer for system design.
- Its live 1:1 mock interviews and mentorship with people ended on 31 May 2026, so human feedback is no longer part of the offer.
- Mockly is live 1:1 coaching for non-native speakers: a UK-based data engineer plays the interviewer, then coaches the English of your answers.
- The two solve different problems. Many candidates will get the most from using both.
Mockly vs Hello Interview: Quick Snapshot
| Dimension | Mockly | Hello Interview |
|---|---|---|
| What it is | Live 1:1 English interview coaching for non-native tech professionals | Self-study interview prep platform for software engineers and managers |
| Main format | 60-minute Google Meet sessions with a human coach | Articles, videos, Guided Practice problems, AI tutor and AI mock interviews |
| Interview rounds covered | Coding, system design, behavioural, leadership, plus HR screens | System design, low-level design, coding, AI-enabled coding, ML system design, behavioural |
| Who gives feedback | Sophie or Tom, UK-based data engineers who teach English to tech professionals | An AI interviewer and AI tutor (human mocks ended 31 May 2026) |
| English coaching | Core focus: phrasing, clarity and structure of spoken answers | Not an English course; Live Practice rates communication as one competency |
| Pricing model | Free 30-min trial; $50 per session or cheaper packs; optional $9.99/month course | Free content; Premium one-time payment from $59 (list price, Oct 2026) |
Hello Interview teaches what to say in a technical interview. Mockly works on how you say it in English.
Where Hello Interview Is Strong
Insight
Hello Interview is built for learning the technical side of interviews in depth, and a lot of it is free to start with.
What Hello Interview offers (checked on its site, October 2026)
- Free learning tracks for System Design, Coding, Low-Level Design, ML System Design, Behavioral and AI-enabled coding. The homepage says you can start free and go deeper when you are ready.
- Premium adds 36 premium videos, System Design, LLD, Coding, AI Coding and Behavioral courses, 66 Guided Practice problems, candidate-reported interview questions and an AI tutor.
- Guided Practice walks you through common system design and low-level design questions step by step, with feedback after each step. It also covers AI coding and behavioural stories.
- Live Practice is an AI mock interview for system design. You talk through your design out loud on a shared whiteboard, answer follow-up questions, then get a hire or no-hire call for your target level and a written report.
- The Live Practice report rates problem navigation, solution design, technical excellence and communication, and you can replay the board, transcript and audio.
- Premium is a one-time payment that does not auto-renew, which is easy to budget for.
Interview tip
If you are still learning how to design a rate limiter or a news feed, Hello Interview's free system design material is a good place to start before paying for anything.
The Gap for Non-Native Speakers
Many non-native engineers already know the technical answer. The problem shows up when they have to say it: the sentence comes out in the wrong order, the trade-off sounds unsure, or a STAR story runs out of words halfway. That is a language and delivery problem, and it needs a different kind of practice.
What changes for a non-native candidate
- No human mock interviews: Hello Interview's live 1:1 mocks and mentorship ended on 31 May 2026. Feedback now comes from an AI interviewer and AI tutor.
- Not an English course: Hello Interview teaches interview content and frameworks. It does not describe grammar, vocabulary or pronunciation coaching.
- Live Practice covers system design: its AI mock interviews are described as system design interviews, so behavioural and HR rounds are practised through Guided Practice instead.
- With Mockly, the coach plays the interviewer for the full round, then switches to coach mode: line-by-line phrasing fixes, ownership language and a personalised drill list.
- Mockly sessions cover coding (problems agreed in advance or randomised on the day), system design on a shared Excalidraw whiteboard, behavioural and leadership rounds.
- Mockly needs only B1+ conversational English. Coaches slow down and rewrite sentences into ones you can actually say under pressure.
Watch Out
Mockly is not a replacement for learning system design. If your blocker is the technical bar itself (for example LeetCode difficulty), Mockly's own advice is to use a coding platform for that part. Mockly is for the moment you know the answer but cannot say it clearly in English.
Free Mini App
Practise explaining a system design out loud in English
Free, no card needed. Practise the spoken English of a tech interview before you book anything.
Try the Mini AppPricing Compared (as of October 2026)
Insight
The two price models are different. Hello Interview sells time-limited or lifetime access to a content library. Mockly charges per live session with a person.
Pricing facts
- Hello Interview: free learning content is available without paying.
- Hello Interview Premium (list price, as of October 2026): $59 for 1 month, $119 for 1 year, $399 lifetime. A limited-time sale during our check showed $47, $89 and $299.
- Hello Interview Premium includes Live Practice AI interviews: 1 with a month, 2 with a year, 10 with lifetime. Extra Live Practice credits are sold separately and come with a money-back guarantee.
- Hello Interview Premium is a one-time payment that does not auto-renew.
- Mockly: a free 30-minute trial with a coach on Google Meet. No card and no subscription.
- Mockly: live 60-minute 1:1 sessions are pay-as-you-go. One session is $50; packs of 5 ($237.50), 10 ($450) or 20 ($850) cost less per session. Credits last 12 months and work with either coach.
- Mockly: Premium is the self-study course at $9.99/month, or $59.99/year, with a 7-day free trial. It does not include a coaching session and you do not need it to book one.
- Mockly: the mini apps (English check, tell-me-about-yourself script, think out loud, LeetCode and system design explainers) are free.
Interview tip
Prices change. Check hellointerview.com/pricing and app.mocklyenglish.com/pricing before you buy.
Honest Pros and Cons
Hello Interview: Pros and Cons
PROS: Deep system design, low-level design and coding content, much of it free; Guided Practice with step-by-step feedback; AI mock interviews for system design with a hire or no-hire report; one-time Premium payment with no auto-renewal; available any time, at your own pace. CONS: Human mock interviews and mentorship ended on 31 May 2026; no English language coaching; AI Live Practice covers system design rounds; you need the discipline to study on your own.
Mockly: Pros and Cons
PROS: Live 1:1 sessions with a human coach who plays the interviewer; feedback on how you phrase and structure answers in English; coding, system design, behavioural and leadership rounds; coaches are UK-based data engineers who teach English to tech professionals; free 30-minute trial with no card; sessions without a subscription. CONS: Not a technical curriculum; two coaches, so less availability than a large platform; $50 per live hour costs more than an AI interview; it will not teach you system design from scratch.
Who Each One Is Best For
Hello Interview is best for
Mockly is best for
FAQ
Questions
More questions? Email us at contact@mocklyenglish.com.
Student success stories
All case studies →How a Java Engineer New to London Prepared System Design English
A Java backend engineer who moved from Korea to London prepared system design and live-coding English - vocabulary, phrases and structure first.
Read storyHow a Backend Engineer in Sydney Prepared for Microsoft in English
A Sydney backend engineer from China prepared Microsoft competency stories and system design in English: outages, metrics, AI agents. No offer claimed.
Read story