Ferramentas online gratuitas
405+ free online tools for PDF, images, SEO, developers, color, and productivity. Fast, browser-based, and private — no signup, no installs, no limits. Search above or browse by category below.
Total tools405Available free tools
Categories15Active categories
Most usedCSV to ExcelPopular right now
Recently addedInterval Music RepeaterNewest tool
Reaction Stoichiometry Calculator
Reaction stoichiometry calculator free — moles and grams from a balanced equation and known amount. Auto-balance, no signup.
AI Email Writer
Draft professional emails with AI using your own OpenAI, Anthropic, Google, or Groq API key.
Raga Scale Practice Drone
Free raga scale practice drone — sustain Sa–Pa tanpura-style tones for Indian classical practice in the browser. No signup.
Background Remover
Free background remover — erase photo backgrounds in your browser. Download transparent PNG or replace with a new color. Private, no upload, no signup.
Audio Noise Reduction Vocal Remover
Free lite noise reduction and karaoke-style vocal remover — preview and download WAV in your browser. Not AI stem separation.
Projectile Motion Calculator
Free projectile motion calculator — find range, max height, and time of flight from speed and launch angle. Instant results in your browser.
Probability Calculator
Calculate basic, complement, union, intersection, conditional, and binomial probabilities with formulas and step-by-step work.
Trending AI Prompts
Browse curated trending AI prompts for ChatGPT, Claude, Gemini, Midjourney, and more. Search, filter, fill variables, and copy free prompt templates.
Thin Content Risk Scanner
Free thin content risk scanner — paste page text and get a quick thin-content risk score with SEO checklist tips. Client-side only.
Data Plotter
Plot data as line, scatter, or bar charts from x,y pairs or separate columns. Enter lab results, calibration curves, or trial data — get an instant SVG chart with axis labels. Free, browser-based.
Hreflang Canonical Checker
Free hreflang and canonical checker — audit conflicts, missing return links, and SEO issues from pasted HTML or a fetched URL.
Sample Size Calculator
Calculate sample size for surveys, mean estimates, A/B tests, and two-group comparisons. Set confidence level, power, margin of error, and effect size. Step-by-step formulas. Free, browser-based.