Tools that make
the hard parts tangible.
Interactive visualizers, estimators and playgrounds for builders — the kind of thing you wish existed when you were stuck on a system-design diagram or a RAG pipeline. Every tool is free, needs no account, and runs entirely on your device.
Consistent Hashing Visualizer
Watch keys rebalance on the hash ring as nodes come and go.
Interactive Capacity Estimator
Back-of-the-envelope math for system design, with the reasoning shown.
RAG Chunking Playground
Paste a document, pick a strategy, see the actual chunks and tokens.
Context Budget & Cost Planner
Model an agent’s context window and see where the tokens (and dollars) go.
Quorum (N/R/W) Explorer
Set N, R and W and instantly see your consistency–availability trade-off.
Availability (Nines) Calculator
Compose services in series and parallel to find your real uptime.
LLM-as-Judge Rubric Builder
Design an eval rubric and generate the judge prompt for it.
Tool-Schema Designer
Build a function-calling tool definition visually, get valid JSON out.
Tools — frequently asked questions
Are these developer tools free?
Yes. Every tool on Vibe Engines is completely free, with no account, sign-up, or payment required. They run entirely in your browser — nothing you type is sent to a server.
Do I need to install anything or create an account?
No. Each tool is a self-contained web page that loads instantly and runs client-side in your browser. There is nothing to install and no login.
Is my data private when I use these tools?
Yes. The tools compute everything locally in your browser. Text, numbers, and documents you enter never leave your device, so you can safely use them with work-related inputs.
Who are these tools for?
They are built for software engineers, backend and AI builders, and anyone preparing for system-design or AI-engineering interviews — interactive visualizers and estimators that make hard concepts tangible.
Can I suggest a tool?
Absolutely. The coming-soon list is shaped by what builders ask for. Use the "Suggest a tool" link on this page to send an idea, and the best ones get built next.
Got a tool you wish existed?
These are built for builders. If there’s an interactive tool that would make your work easier, tell me — the best ideas become the next ones I ship.
Suggest a tool →