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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
pOH Calculator
pOH calculator free — find pOH, pH, and [OH⁻] from hydroxide concentration or strong base molarity. Instant, no signup.
Used 0 times•Updated never
Buffer Calculator
Buffer calculator free — Henderson-Hasselbalch pH for acid and base buffers. Solve pH, pKa, or concentrations. Instant, no signup.
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Empirical Formula Calculator
Empirical formula calculator free — find simplest formula from mass % or element masses. Mole ratios in your browser, no signup.
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Molecular Formula Calculator
Molecular formula calculator free — find true formula from empirical formula and molar mass, or composition plus experimental M. No signup.
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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.
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Charles' Law Calculator
Charles' law calculator free — solve V1/T1=V2/T2 for volume or temperature at constant pressure. K, °C, L, mL. No signup.
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Combined Gas Law Calculator
Combined gas law calculator free — solve P1V1/T1=P2V2/T2 for any unknown. Pressure, volume, temperature units. No signup.
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Reaction Stoichiometry Calculator
Reaction stoichiometry calculator free — moles and grams from a balanced equation and known amount. Auto-balance, no signup.
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Atomic Mass Calculator
Atomic mass calculator free — IUPAC element lookup or weighted isotope average. Atomic number and u/g/mol. No signup.
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Electron Configuration Generator
Electron configuration generator free — full and noble-gas notation for any element. Aufbau rules + exceptions. No signup.
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Periodic Table Explorer
Interactive periodic table with element details, atomic mass, and electron configuration for all 118 elements.
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