About Periodic Table Online
A free, comprehensive chemistry resource — interactive visualisations, in-depth learning materials, and printable references for students and educators worldwide.
Our Mission
Periodic Table Online was created with a singular purpose: to make chemistry education accessible, engaging, and comprehensive for learners worldwide. We believe that understanding the fundamental building blocks of matter — the elements — is essential for scientific literacy and critical thinking.
Our platform bridges the gap between complex chemical concepts and intuitive understanding through interactive visualisations, real-time molecular analysis, carefully curated educational content, and free downloadable reference materials. Whether you're a high school student encountering chemistry for the first time, a university student diving deep into organic chemistry, or a lifelong learner curious about the world around you, our tools are designed to support your journey.
What We Offer
Interactive Periodic Table
Explore all 118 elements with detailed properties including atomic mass, electron configuration, physical states, and real-world applications. Colour-coded visualisation identifies element groups, and a suite of interactive overlays lets you go deeper:
- 12 Trend Modes — visualise atomic radius, electronegativity, ionization energy, electron affinity, density, melting & boiling points, atomic mass, covalent radius, van der Waals radius, electrical conductivity, and ionization potential as colour gradients across the table.
- Discovery Year Timeline — drag a slider to travel through the history of element discovery, dimming elements found after your chosen year.
- Isotope Decay Mode — colour every element by its primary radioactive decay mode (alpha, beta, electron capture, or stable).
- Temperature Slider — watch elements change phase between solid, liquid, and gas in real time.
- Interactive 2D Bohr model diagrams and 3D Google model-viewer visualisations for every element.
Material Composition Analysis
Search for any material — from water to steel, from caffeine to DNA — and discover its elemental composition. Our AI-powered search connects to scientific databases including PubChem and Materials Project to provide accurate molecular data and force-directed structure visualisations with real chemical bonds.
Free Printable PDF Charts
Download professionally designed A4 landscape periodic table PDFs — all free, no sign-up required. Choose from a minimal exam version, full colour-coded chart, electron configuration reference, periodic trends sheet, heatmaps, and more.
Chemistry Calculators
Solve common chemistry equations with 8 interactive calculators. Calculate molarity, molar mass, ideal gas law, pH, dilution, stoichiometry, percent composition, and Gibbs free energy with support for reverse solving and step-by-step explanations.
Unit Converter
Convert between scientific units with precision. Supports temperature, length, mass, volume, energy, pressure, and time conversions with educational explanations for each unit type. Results always display in decimal format for clarity.
Educational Blog
In-depth articles on chemistry fundamentals, element discoveries, molecular bonding, and real-world applications. Each article is written to be accessible while maintaining scientific accuracy.
Our Approach to Education
We follow evidence-based educational principles:
- Visual Learning: Interactive visualisations help cement abstract chemical concepts — trend colour gradients, discovery year timelines, isotope decay maps, Bohr model diagrams, molecular structure displays, and colour-coded element categories support multiple learning styles.
- Historical Context: The element discovery slider lets learners explore the history of chemistry chronologically — from the ancient recognition of iron and copper to the synthesis of modern superheavy elements.
- Active Exploration: Rather than passive reading, users can search, click, compare, and manipulate data — promoting deeper understanding through engagement.
- Contextual Learning: We connect abstract chemistry to everyday materials, showing how elements combine to form the substances around us — from the caffeine in your coffee to the hemoglobin in your blood.
- Offline-Ready Resources: Our free downloadable PDF charts let learners take accurate periodic table references anywhere — to class, the library, or exam revision sessions — without needing an internet connection.
- Accurate Data: We source chemical data from authoritative databases including PubChem (NIH), ChEMBL (EMBL-EBI), and Materials Project (Berkeley Lab).
Who We Serve
- Students: From middle school through university — studying for exams, completing homework, and exploring chemistry concepts independently.
- Educators: Teachers and professors using our interactive periodic table as a classroom resource. The printable PDF charts are ready-to-use handouts, and the trend and discovery timeline overlays support engaging lessons.
- Professionals: Scientists, engineers, and healthcare professionals referencing comprehensive element data for their work.
- Curious Minds: Anyone interested in understanding how everyday substances are composed at the atomic level, or how our understanding of the elements evolved over centuries.
Data Sources & Accuracy
All content on Periodic Table Online is 100% original — written and designed by our team. We integrate scientific data from authoritative peer-reviewed sources to ensure accuracy.
- PubChem (National Institutes of Health) — For accurate molecular formulas, structures, and compound properties.
- ChEMBL (European Molecular Biology Laboratory) — For verified chemical bond information and molecular structures.
- Materials Project (Lawrence Berkeley National Laboratory) — For authoritative materials properties and compositions.
- IUPAC (International Union of Pure and Applied Chemistry) — For official element names, symbols, and atomic weights.
- USDA FoodData Central — For accurate food composition data in our material analysis.
All blog posts, interactive tutorials, educational explanations, printable PDF charts, and learning guides are created entirely by our team. Each article provides unique insights and pedagogical approaches.
Have Questions or Feedback?
We're always looking to improve our platform and help learners succeed.
Contact Us