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Dataslope
What Dataslope is
Dataslope is a free browser platform for learning programming and data skills and preparing for coding interviews. It offers 32 interactive courses, six role-based interview tracks, more than 300 graded coding and SQL challenges, and more than 650 in-lesson exercises. Its browser SQL workbench supports querying, schema editing, and sample-database exploration. Listed environments include Python, R, JavaScript, TypeScript, HTML, React, PHP, C, C++, Java, C#, PostgreSQL, SQLite, DuckDB, Git, and Bash. Languages and databases run locally through WebAssembly, processing code and queries on the user’s machine. Guests can use courses, interview preparation, playgrounds, and quizzes without an account. Optional members can sign in with Google, GitHub, or email and password. The Free Member plan includes 100 MB of cloud storage and 10 Ask AI messages per 24 hours; cloud saves and shared playgrounds are subject to inactivity cleanup. Sharing creates a link to a private copy, while guest links expire after 30 days. There is no real-time collaboration, full-stack runtime, or deployment option listed.
Who it suits
It suits learners practicing programming, SQL, data skills, or role-specific interview material in a browser. Guests fit users wanting no account, while members add cloud saves and shared playgrounds.
What it does well
- 32 free interactive courses
- Six role-based interview tracks
- Hundreds of graded coding and SQL challenges
- Runs languages and databases locally in browser
- Guest access requires no account
What to know first
- No real-time collaboration
- Guest sharing links expire after 30 days
- Member cloud data may be cleaned after inactivity
- No deployment options or full-stack runtime
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Guest | No account needed · Full access to courses, interview prep, and playgrounds · Unlimited code executions · Local browser saves only · No cloud storage · Share links expire after 30 days · No Ask AI messages | Free |
| Free Member | Free forever · Everything in Guest · 100 MB cloud storage across playgrounds · Cloud saves and shared playgrounds may be deleted after a month of inactivity · Up to 10 Ask AI messages per rolling 24 hours | Free |
As dataslope.com lists them, read 8 Oct 2026. The maker's own page has the final word.
Verdict
Dataslope combines structured lessons, interview preparation, browser exercises, and local code execution. Its guest access is straightforward, while cloud storage and sharing are limited to the free member setup.
Facts from Dataslope's own pages
- AI assistant
- The optional Ask AI assistant sends a user's question and relevant page context to a third-party AI provider, and the privacy policy says conversations are not stored unless the user rates an answer. · dataslope.com, 8 Oct 2026
- Challenges
- The homepage lists more than 300 graded coding and SQL challenges and more than 650 in-lesson exercises. · dataslope.com, 8 Oct 2026
- Courses
- It offers 32 free browser-based courses with interactive code blocks. · dataslope.com, 8 Oct 2026
- Deployment options
- none · dataslope.com, 22 Sept 2026
- Execution
- The privacy policy says languages and databases run locally in the browser through WebAssembly, and code and queries are processed on the user's machine. · dataslope.com, 8 Oct 2026
- Free plan
- Yes · dataslope.com, 22 Sept 2026
- Full-stack runtime
- No · dataslope.com, 22 Sept 2026
- Interview preparation
- It offers six free role-based interview tracks for analyst, data, machine learning, and backend or software engineering roles. · dataslope.com, 8 Oct 2026
- Languages and databases
- The homepage lists Python, R, JavaScript, TypeScript, HTML, React, PHP, C, C++, Java, C#, PostgreSQL, SQLite, DuckDB, Git, and Bash as browser-supported environments. · dataslope.com, 8 Oct 2026
- Plan availability
- The terms say all memberships are currently free with no paid plan and that free account features may be restricted or removed based on capacity. · dataslope.com, 8 Oct 2026
- Playground
- Its in-browser SQL workbench lets users query, edit schemas, and explore sample databases. · dataslope.com, 8 Oct 2026
- Privacy
- The privacy policy says Dataslope does not sell or rent stored account information and that guest use does not require personal information such as a name or email address. · dataslope.com, 8 Oct 2026
- Private projects
- Yes · dataslope.com, 22 Sept 2026
- Purpose
- Dataslope is a browser-based platform for learning programming and data skills and preparing for coding interviews. · dataslope.com, 8 Oct 2026
- Real-time collaboration
- No · dataslope.com, 22 Sept 2026
- Sharing controls
- link_access · dataslope.com, 22 Sept 2026
- Sharing
- Playground sharing creates a link to a snapshot that recipients can open as their own private copy; guest links expire after 30 days. · dataslope.com, 8 Oct 2026
- Sign-in
- Guests can use courses, playgrounds, and quizzes without an account; optional accounts can be created with Google, GitHub, or email and password. · dataslope.com, 8 Oct 2026
- Support
- The site directs users to GitHub discussions for questions and GitHub for bug reports. · dataslope.com, 8 Oct 2026
Where Dataslope stands on Freedom251
- Coding Playgrounds#90 of 138