A living evidence board
Drag clues around, zoom into the web of connections, and watch conclusions form — like the string-and-corkboard wall of every great detective, minus the string burns.
From the rooms of 221B
Think like Sherlock.
Deduce with AI.
Paste any mystery into the Sherlock Deduction Board and watch Gemini AI pull out the clues, pin them to a living evidence board, draw the connections between them, and reason its way to a conclusion — while Holmes, Watson, and experts of your own invention weigh in from the sidelines.
Free to use — AI included. Everything runs in your browser.
From story to solved in three steps
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1
Tell the board a mystery
Type your own case, paste a classic whodunit, or let the board conjure a fresh mystery for you with one click.
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2
Watch the deduction unfold
AI extracts the key clues and pins them to an interactive canvas, connecting the evidence with animated threads of reasoning.
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3
Interrogate the conclusion
Read the full rationale, add your own observations, and consult AI experts to challenge or confirm the verdict.
What makes it fun
AI consultants on call
Chat with Sherlock Holmes and Dr. Watson, or create your own specialists — a forensic chemist, a retired jewel thief, Nikola Tesla — and ask what they make of the evidence.
Two deduction engines
Use fast Traditional analysis, or switch on the Object-Oriented engine where every clue becomes an intelligent agent that debates the others to crack the case.
Group discussions
Put your whole panel of consultants in one room, set a topic, and let them argue their way to a consensus — then apply it to the board.
Your observations count
Add your own clues, remove red herrings, and re-run the conclusion. The board reasons with your version of the evidence.
Pick your AI model
Choose between Gemini models — from lightning-fast Flash-Lite to deep-thinking Pro — or plug in any custom model ID as new ones ship.
Private by design
Elementary Tools has no accounts and no tracking pixels. Your stories, settings, and progress live in your browser's local storage — nothing you write is kept on our servers. The AI is included and free: open any tool and start deducing. Read the full privacy policy.
A toolbox for work — and for play
💼 The Consulting Room — professional tools
Moriarty's Web
A mind-map for reasoning: claims, premises, thread strengths, and named fallacies — exportable to Markdown.
Eliminate the Impossible
Root-cause analysis, Holmes-style — for stubborn bugs, odd outages, and decisions that won't resolve.
The Reichenbach Timeline
Incident reports and post-mortems become interactive chronologies with per-person threads.
Mycroft's Memory Palace
The method of loci for speeches, terminology, and lists — with a practice drill and saved palaces.
Watson's Case Files
A development editor for mystery writers: plot holes, fair-play audit, and an editorial interview.
Sherlock's Mind Palace
A full-screen spatial memory palace: draggable rooms, AI-planted scenes, and a walk-through practice mode.
Toby's Trail
Goals become scent-trails of ordered milestones — with the first action you can take today.
🎭 The Game Room — for the fans
Lestrade's Lineup
An AI whodunit: interrogate five suspects, catch the one lie, and make your accusation.
The Science of Deduction
Deduce a stranger from their visible details and have Holmes grade your reasoning, claim by claim.
Dancing Men Cipher
Secret messages in the famous stick-figure cipher — plus Caesar, Vigenère, and a code cracker. Instant, in your browser.
Frequently asked questions
- Is it really free?
- Yes. The site, the tools, the games, and the AI behind them are free to use — no account, no payment details, nothing to configure.
- Do I need to install anything?
- No — everything runs in your browser on desktop or laptop. Open a tool and it simply works.
- Where do my stories go?
- Your stories and settings stay in your browser's local storage. Text you submit to an AI feature is processed to generate the response and is not kept by Elementary Tools.
- Can I write my own mysteries?
- Absolutely — that's the best part. Paste anything from a three-sentence riddle to a full short story, and see what the board deduces. You can also generate mysteries with one click.
A fresh case awaits
The game is afoot
Your first case is waiting on the board.
🔎 Launch the Deduction Board