Quick Answer
Interview Query is interview preparation for data science, machine learning, data engineering and analytics roles: a bank of over 1,000 questions, over 6,000 company guides, 9 learning paths, over 50 take-home challenges, community mock interviews and a data job board. Its pricing page showed $79 a month (cancel any time) and a $199 option when we checked on 10 November 2026. Mockly English is live 1:1 coaching with practising data engineers who also teach English, so they can run a SQL, data modelling, system design or behavioural round in English and fix how you explain it, at $50 a session after a free 30-minute trial. Use Interview Query to learn what to say; use Mockly to say it clearly in English.
What makes Mockly English different
Mockly English is built for one job: getting non-native engineers and data professionals through tech interviews, and through meetings, in English. Your coach is a practising UK data engineer who also teaches English. They run the real round (coding, system design, SQL and data, behavioural, HR), then correct your English line by line and have you say it again. The first 30 minutes are free with no card; after that it is $50 a session, with no subscription.
⚡ Quick Stats
What Interview Query Offers
These facts come from Interview Query's pricing page, checked on 10 November 2026.
- Over 1,000 interview questions, which it says are posed by recruiters, across product sense and analytics, algorithms for ML and engineering roles, SQL and analytics, Python, statistics and A/B testing, ML system design and modelling case studies.
- Over 6,000 guides to company hiring processes, salaries and questions.
- 9 learning paths with over 350 lessons, and over 50 real take-home challenges with solutions.
- Mock interviews with peers and mentors from its community, and coaching from people who have interviewed and hired for data roles.
- A data science job board.
- Pricing: the page showed $79 a month, cancel any time, and a $199 price. Check the page for exactly what each one includes.
Interview Query is strong on content: what data interviews ask and what a good answer contains. It does not describe English coaching on the pages we read, so we say only that.
Where Data Interviews Test Your English
Data roles have more talking than many candidates expect. These are the moments where non-native speakers lose points even with the right answer:
- Product and metrics questions. “What would you track to improve this feature?” is a structured spoken answer, not a calculation.
- Explaining an A/B test result to someone who is not a statistician: what you found, how sure you are, what you recommend.
- Talking through SQL while you write it, including why you chose a join or a window function.
- Take-home presentations, where the slides are fine but the spoken walkthrough is long and unsure.
- Stakeholder stories in the behavioural round: pushing back on a bad metric, handling a data quality incident.
Insight
A general English teacher can correct grammar in your A/B test explanation. A coach who works with data every day can also tell you when “the result is significant” is the wrong thing to say, and what a hiring manager would ask next.
Free Mini App
Practise a 60-second answer
Say a metrics or behavioural answer in 60 seconds and get feedback on structure and English. Free, no account.
Try the Mini AppSide by Side
| Interview Query | Mockly English | |
|---|---|---|
| What it is | Data science and ML interview prep: questions, guides, courses, take-homes | Live 1:1 tech interview English and business English coaching |
| Who it is for | Data scientists, ML engineers, data engineers, analysts | Non-native English speakers in tech, including data engineers and data analysts |
| Main format | Self-study platform, plus community mocks and coaching | 60-minute 1:1 sessions on Google Meet |
| English feedback | Not described on the pages we read | Line-by-line corrections, then you say it again |
| Technical coverage | Broad: SQL, Python, statistics, product, ML, case studies | The English of SQL and data, coding, system design, behavioural and HR rounds, coached by data engineers |
| Price (as checked) | $79/month, cancel any time; a $199 option shown | $50 a session; packs of 5, 10 or 20; free 30-minute trial |
| Best for | Knowing what to study and what good answers contain | Saying those answers clearly and confidently in English |
A Four-Week Plan Using Both
- Week 1: use Interview Query's company guide for your target role. Book Mockly's free trial and answer two practice questions out loud to find your English habits.
- Weeks 1–3: work through Interview Query questions for your weakest topic. Say every answer out loud, not only in your head.
- Week 2: one Mockly session on SQL or a metrics case: you explain while you solve, the coach fixes the English.
- Week 3: one Mockly session on your behavioural stories, especially stakeholder and incident stories.
- Week 4: a full mock round with a Mockly coach, and a peer mock on Interview Query for a different voice.
Mockly prices (as of November 2026)
- 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.
Verdict
They solve different problems. Interview Query tells data candidates what interviews ask and what good answers look like. Mockly English makes sure you can say those answers clearly in English, with feedback from engineers who work with data. If English is not your first language, use both.
Talk to an engineer-coach first
Book a free 30-minute Google Meet with Sophie or Tom. No card, no subscription. You practise a short interview-style prompt in English and leave with a plan for what to work on next.
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