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Developer tools for AI engineering
Calculators, analyzers, and utilities for building with LLMs. Everything runs in your browser — no signup, and your data never leaves your machine.
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Calculators, analyzers, and utilities for building with LLMs. Everything runs in your browser — no signup, and your data never leaves your machine.
Compare Claude, GPT, Gemini and DeepSeek prices — see your monthly cost at any volume.
Cost & PricingPaste a prompt or set token counts and get the exact cost on every major model.
Cost & PricingModel a full agentic coding session — turns, tool calls and growing context, priced.
Cost & PricingFind the breakeven point where prompt caching starts saving you money, per provider.
Cost & PricingSee how much of your workload qualifies for 50% batch pricing and what you would save.
Cost & PricingForecast your engineering team's monthly AI spend from team size and usage profiles.
Cost & PricingFind tasks where a cheaper model does the job — and how much you save by routing them.
Cost & PricingGPU rental versus API tokens: find your breakeven volume before buying hardware.
Cost & PricingPrice your RAG pipeline: document indexing cost plus monthly query embedding spend.
Cost & PricingCompare fine-tuning costs against long-prompt overhead to find which approach wins.
Cost & PricingAI review versus human hours: the monthly cost of reviewing your team's pull requests.
Cost & PricingA guided diagnostic that finds what blew up your AI bill — loops, cache misses or retries.
Cost & PricingPer-seat plans or pay-per-token? Simulate your team's usage curve and find the winner.
Cost & PricingEstimate the energy and CO2 of your monthly token volume, with honest uncertainty ranges.
Cost & PricingPrice AI image generation per image and per month — gpt-image and Gemini rates, verified.
Cost & PricingSora per-second pricing by resolution — price a clip, a campaign, or a monthly pipeline.
Cost & PricingWhisper and 4o-transcribe pricing per minute — price calls, podcasts and meeting archives.
Cost & PricingGrounded search costs $10-35 per 1k queries — price your agent's search habit accurately.
Cost & PricingSplit traffic across models and see your true blended rate per million tokens.
Cost & PricingPrice a complete task — calls, retries and context included — across models honestly.
Count GPT and Claude tokens in any text — free, instant, and it never leaves your browser.
Tokens & ContextSee how your system prompt, history and files fill a 200k window — and when you overflow.
Tokens & ContextConvert between tokens, words, characters and pages with per-language ratios.
Tokens & ContextEvery major model's context window, max output, price and speed in one sortable table.
Tokens & ContextStrip token waste from prompts — whitespace, markdown decoration and duplicate lines.
Tokens & ContextDrop a Claude Code or OpenAI session file and get a per-turn token and cost breakdown.
Tokens & ContextRender your markdown with a heatmap showing exactly which blocks burn the most tokens.
Tokens & ContextSee how retrieval accuracy degrades as context fills, using published benchmark data.
Tokens & ContextSee how much summarizing conversation history every N turns saves on long sessions.
Tokens & ContextJSON versus YAML versus minified: the token cost of the same data in each format.
Tokens & ContextAllocate a token budget across identity, rules, examples and tools — see what fits.
Tokens & ContextSliding window versus running summary: token and cost math for chat memory designs.
Tokens & ContextHow many more tokens the same text costs in 20+ languages, with live samples.
Tokens & ContextThe same function tokenized across Python, JavaScript, Go and Rust — compared.
Tokens & ContextVisualize chunk size and overlap on your document — chunk count, waste and query cost.
Tokens & ContextConvert tokens per second into words per minute, pages per hour and time-to-read.
Answer eight questions and get a well-structured CLAUDE.md or AGENTS.md for your repo.
Agentic DevelopmentPick MCP servers and get correct config JSON for Claude Code, Cursor and OpenCode.
Agentic DevelopmentGrade your system prompt A to F: contradictions, vague verbs, bloat and missing specs.
Agentic DevelopmentCheck provider tier limits against your agent fleet and find out when you hit 429s.
Agentic DevelopmentPaste any provider error and get the cause, fix checklist and correct retry strategy.
Agentic DevelopmentTokens per second by model: estimate how long any output length takes to stream.
Agentic DevelopmentMonte Carlo your agent's retry and loop behavior to see p95 spend and runaway risk.
Agentic DevelopmentA five-question quiz that recommends the right model for your task, latency and budget.
Agentic DevelopmentTranslate API requests between OpenAI and Anthropic formats with per-line mapping.
Agentic DevelopmentBuild function-calling schemas visually — valid JSON for OpenAI, Anthropic and MCP.
Agentic DevelopmentInteractive visualization of how temperature, top-p and top-k reshape token sampling.
Agentic DevelopmentPretty-print agent session logs: threaded turns, tool calls and diffs, all local.
Agentic DevelopmentGrade your existing CLAUDE.md or AGENTS.md A-F: contradictions, bloat and dead rules.
Agentic DevelopmentThe hidden token tax of tool definitions — per provider, per tool, per call, verified.
Agentic DevelopmentDesign exponential backoff with jitter — visualize timing, cost and worst-case delay.
Agentic DevelopmentBuild tool allowlist and denylist configs for coding agents — safe defaults included.
Agentic DevelopmentHeuristic scan of templates and tool outputs for injection patterns — fully local.
Agentic DevelopmentBuild a structured evaluation rubric and export it as JSON or markdown for your evals.
Agentic DevelopmentGenerate MCP server boilerplate in TypeScript or Python from your tool definitions.
Agentic DevelopmentCheck model JSON output against your schema — type errors, missing fields, extras.
Decode and verify JWTs entirely in your browser — your token never touches a server.
Engineering UtilitiesConvert between JSON, YAML and TOML with instant validation and clear error lines.
Engineering UtilitiesBuild cron expressions visually or paste one to get plain English and next run times.
Engineering UtilitiesGenerate UUIDv4, sortable UUIDv7, ULIDs and NanoIDs with format anatomy explained.
Engineering UtilitiesDebug HMAC webhook signatures locally — Stripe, GitHub and generic SHA-256 presets.
Engineering UtilitiesTest regular expressions with live highlighting and a plain-English pattern breakdown.
Engineering UtilitiesCompare text or JSON semantically — word-level highlights, fully in your browser.
Engineering UtilitiesPing major AI provider endpoints from your browser and compare response times live.
Engineering UtilitiesWill that model fit on your GPU? VRAM needs by parameter count, quantization and context.
Engineering UtilitiesScan code for leaked API keys, tokens and credentials — entirely in your browser.
Engineering UtilitiesPaste a curl command for any AI API and get Python, TypeScript and Go SDK code.
Engineering UtilitiesEncode and decode Base64, Base64url, URL and hex — instant, private, bidirectional.
Engineering UtilitiesConvert epoch timestamps to human dates across timezones, with a live now ticker.
Engineering UtilitiesEvery HTTP status code explained, with AI-API-specific notes on 429s, 529s and timeouts.
Engineering UtilitiesSHA-256, SHA-512 and MD5 for text or files — computed locally with WebCrypto.
Engineering UtilitiesEntropy bits and realistic crack-time estimates — your password never leaves the page.
Engineering UtilitiesDecompose any URL into parts with a query-parameter table and encoding diagnostics.
Engineering UtilitiesRun JSONPath queries against pasted JSON with live results and syntax help.
Engineering UtilitiesPaste CSV or TSV and get a clean, aligned markdown table — with alignment controls.
Engineering UtilitiesIdentify any AI vendor key by its prefix — sk-ant, ghp, AKIA — with security notes.
Engineering UtilitiesSymbolic to octal permissions and back, with a visual permission grid and presets.
Engineering UtilitiesIs that user agent an AI crawler? GPTBot, ClaudeBot and friends — plus robots.txt rules.
Engineering UtilitiesWCAG AA and AAA contrast checking with fix suggestions — for accessible interfaces.
Engineering UtilitiesHeuristic best-practice checks: layer order, cache busting, root user, image size.
Generate a company AI tool usage policy tuned to your industry and compliance needs.
Team & GovernanceIncident timelines and uptime comparison for Anthropic, OpenAI and Google AI APIs.
Team & GovernanceGenerate a phased adoption plan for agentic coding tools across your engineering org.
Team & GovernanceAssign plan tiers to developers based on their usage distribution — stop overpaying.
Team & GovernanceTurn your monthly numbers into a clean markdown spend report finance will accept.
Team & GovernanceBuild a weighted comparison matrix for AI vendors — criteria, weights, scores, verdict.
Team & GovernanceA 12-question maturity quiz scoring your team's readiness for agentic development.
Team & GovernanceDefine per-team and per-developer budget rules and export them as enforceable config.
Team & GovernanceStructured postmortem template for AI outages and cost incidents — blameless format.
Team & GovernanceWhat 99.9% really allows: downtime per month, SLA credit math, composite SLAs.
Team & GovernanceControl checklists by compliance regime — what auditors actually ask about AI usage.
Team & GovernanceDeprecation and retirement dates for major models — plan migrations before EOL.
Team & GovernanceMap SOC 2, HIPAA and GDPR controls to your AI usage — gaps surfaced explicitly.
Team & GovernanceCompute adoption KPIs from your numbers: sessions per dev, cost per PR, DAU per seat.
Team & GovernanceSplit a shared AI bill across teams and projects with defensible allocation rules.
Team & GovernanceBuild an onboarding curriculum for agentic coding — week-by-week, role-aware.
96 tools live · across 5 categories — all free, all client-side.