免费在线工具
268+ 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 tools26810.8K total uses
Categories13Active categories
Most usedJSON Formatter4.1K uses
Recently addedExperiment RandomizerNewest tool
RSA Decrypt
Decrypt RSA-OAEP JSON payloads with your private key, including hybrid RSA + AES-GCM ciphertext.
Used 2 times•Updated 43 minutes ago
Expense Tracker
Log daily expenses by category, see spending totals, and review a breakdown — saved in your browser.
Used 2 times•Updated 33 minutes ago
Scientific Calculator
Perform basic and scientific calculations with trigonometry, logarithms, powers, and degree or radian mode.
Used 2 times•Updated 7 minutes ago
Molecular Formula Calculator
Molecular formula calculator free — find true formula from empirical formula and molar mass, or composition plus experimental M. No signup.
Used 2 times•Updated 7 minutes ago
Boyle's Law Calculator
Boyle's law calculator free — solve P1V1=P2V2 for pressure or volume at constant temperature. atm, kPa, L, mL. No signup.
Used 2 times•Updated 41 minutes ago
Population Growth Calculator
Calculate population growth with exponential and logistic models — solve for N, growth rate r, time, or N₀ with projections and doubling time. Free, browser-based.
Used 2 times•Updated 42 minutes ago
Phylogenetic Tree Generator
Build phylogenetic trees from distance matrices, aligned DNA sequences (UPGMA), or Newick strings — SVG diagram, ASCII tree, and export. Free, browser-based.
Used 2 times•Updated 7 minutes ago
GCD Calculator
Find the greatest common divisor (GCD) and LCM of two or more positive integers with Euclidean algorithm steps and prime-factor method.
Used 2 times•Updated 35 minutes ago
Statistics Calculator
Compute mean, median, mode, standard deviation, variance, quartiles, range, and more from any dataset with step-by-step formulas.
Used 2 times•Updated 44 minutes ago
Star Distance Calculator
Calculate star distance from parallax or magnitude. Convert between parsecs, light-years, AU, and km. Free, instant, browser-based astronomy tool.
Used 2 times•Updated 45 minutes ago
Soil Density Calculator
Calculate soil bulk density, moisture content, porosity, and void ratio from sample mass and volume. Supports metric (g, cm³) and imperial (lb, ft³). Free, browser-based.
Used 2 times•Updated 10 minutes ago