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Every tool, by what you want to do.

21 free tools for working with AI, each built for one job. Say what you are trying to do, or find the moment you are at: before you ask, before you paste, or once the answer is back.

Find a tool

Get a better prompt

Before you ask the AI

  1. Fix a rough prompt in one clickPrompt Improver NewUse it when you have a quick prompt and want a clear one now, with no questions to answer first.Your prompt rebuilt as a brief, with a blank for each detail the AI would guess.Free
  2. See what your prompt is missingPrompt GraderUse it when answers keep coming back vague, generic or off, and you want to know why.A score out of 10, a plain question for each gap, and a better prompt as you answer.Free, AI part needs a key
  3. Write a prompt from scratchPrompt BuilderUse it when you know the job but not how to ask for it, and the box is empty.A few questions, then a prompt that covers all ten checks.Free
  4. Start from an expert promptPrompt templatesUse it when the job is a common one: a summary, an email, a report, an analysis, a plan.Ready-made prompts for work, each with blanks to fill in.Free
  5. Break a big job into stepsWorkflow PlannerUse it when the job is too big for one prompt: research, then draft, then review.The steps in order, an expert prompt for each, and each answer carried into the next.Free

Set up your AI once

So you stop repeating yourself

  1. Tell your AI how you like answersCustom InstructionsUse it when you paste the same background into every chat: your role, your tone, your rules.Standing instructions for ChatGPT, Claude, Gemini or Copilot, and where to put them.Free
  2. Build a custom GPT, Project or GemAssistant BuilderUse it when you want an assistant your team can reuse for one job, with its own rules and files.Instructions that keep their rules, first messages, files to attach and tests.Free
  3. Keep the prompts that workMy PromptsUse it when a prompt worked and you want it again next week, with every version kept.A private prompt library in your browser, with versions, tags and search.Free

Before you paste

Protect what goes in

  1. Hide client names and numbersSafe PasteUse it when the text mentions real people, clients, accounts or deals, and you are about to paste it into an AI.Placeholders in place of names, emails and numbers, and the real ones put back in the answer.Free
  2. Check a long document fitsToken CounterUse it when you want to paste a long report, contract or transcript and are not sure it fits.Tokens, words and pages, the fit on every model, and a splitter for long text.Free

Check the answer

Before it goes out under your name

  1. See if the AI did what you askedInstruction CheckUse it when an answer came back and you need to know it followed every rule in your prompt.Each rule kept or broken, and the facts it added that you never gave it.Free
  2. Check the facts in an AI answerFact Check ListUse it when an answer has numbers, names, quotes or sources that will go out under your name.Every claim to check, riskiest first.Free
  3. Make it not sound like AIRobot-Speak CheckerUse it when a draft reads like ChatGPT wrote it, and it has to sound like you.Every phrase that gives it away, the easy fixes made, and a line to stop them next time.Free
  4. Paste answers cleanly into Word or emailCopy CleanerUse it when the answer is full of stars and hashes when you paste it into Word, Outlook or Slack.Real headings, bold and bullets, ready for where it is going.Free

Pick a model and price it

Which AI, and what it costs

  1. Try one prompt on several modelsModel CompareUse it when you want to see which AI answers your kind of task best before you choose.Up to six answers side by side, with speed and cost.Needs a key
  2. Estimate your monthly AI billAI Cost CalculatorUse it when you are building with AI, or budgeting for it, and need a monthly number.The bill for your volume on every major model.Free
  3. See what every model costsAI price indexUse it when you want today's prices for the major models in one place.Every major model's price side by side, checked against the vendors' pages.Free

For teams and builders

Prompts in products, code and shared libraries

  1. Test a prompt on real examplesPrompt TesterUse it when you changed a prompt that runs in a product and need proof it got better.Your prompt run on many examples, with what each change fixed or broke.Needs a key
  2. See what changed between versionsVersion CompareUse it when two versions of a prompt and you need to see every change and its effect.Every changed word, with the effect on length, cost and score.Free
  3. Check a chatbot keeps its rulesChatbot Safety TestUse it when customers will talk to your chatbot, and some will try to trick it.Attacks run against your system prompt, and what leaked.Free, AI part needs a key
  4. Review the prompts in your codePrompt LinterUse it when your app sends prompts to a model and you want them reviewed like code.Injection risks, JSON that will not parse and outdated model ids, with the line and the fix.Free
  5. Tidy a team's prompt documentLibrary AuditUse it when your team keeps prompts in a shared doc and it has grown messy.A health score, near-copies, private details and the prompts to fix first.Free
  6. Brief a coding agentAgent Brief CheckUse it when you are about to hand a task to Claude Code, Cursor or Copilot.What the brief is missing, what is risky, and a better brief.Free

Close calls, settled

Prompt Improver, Prompt Grader or Prompt Builder?

All three end with a better prompt. The Prompt Improver is the fast one: paste, and it hands back your prompt rebuilt as a brief with a blank for each missing detail. The Prompt Grader shows you why: a score out of 10, a question for each gap, and an AI review if you want one. The Prompt Builder is for an empty box, when you know the job but not how to ask.

Instruction Check or Fact Check List?

Instruction Check holds an answer to your prompt: which rules it kept, which it broke, and what it added that you never gave it. The Fact Check List holds an answer to the world: every number, name, quote and source in it that you should confirm before it goes out.

Robot-Speak Checker or Copy Cleaner?

The Robot-Speak Checker fixes the words, the phrases that make a draft read like AI. The Copy Cleaner fixes the formatting, the stars and hashes an answer brings with it into Word, Outlook or Slack.

Do I need an API key?

Not for most of them. Every tool marked Free runs without one. A key is a code from an AI company that lets a tool run models on your account, usually for a fraction of a cent; Settings shows how to get a free one.

Does what I type leave my browser?

For most tools, no: they run on the page itself, so a prompt, a client name or an answer you paste stays on your computer. Six tools read your text on our server when you press their button, because that is where their engine runs, and keep none of it: Instruction Check, the Assistant Builder, the Workflow Planner, the Prompt Linter, Library Audit and Agent Brief Check. The privacy page says exactly what each one reads.