Periodic table
Visual reference of all 118 elements color-coded by category. Click any element to see atomic number, mass, electron configuration, and category. Filter by symbol, name, or atomic number.
Click an element
Reading the table
Rows are periods (energy shells); columns are groups (similar chemistry). Color coding shows category — alkali, alkaline, transition, halogen, noble, etc.
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Browse or search
Filter by symbol, name, or atomic number.
Inputs are treated as UTF-8 throughout the pipeline and validated client-side as you type — nothing dispatches until the value is well-formed.
searchinpututf-8client-sidevalidatedsearch · textAu · setGold (79)
loaded · parsedclient-side - 02
Click element
The detail panel shows atomic number, mass, config.
Each toggle re-computes through a memoised hook, so flipping options never resets your input and the UI stays snappy on large inputs.
clickoptionslivememoisedtogglesclick · memoisedAu · live196.97 u
options set · memoisedlive - 03
Identify category
Color matches the legend at the bottom.
Randomness — where used — comes from
crypto.getRandomValues, neverMath.random. Heavy work sits inuseMemo.catcomputeinstantlocaldeterministiccat · instanttransition · computedtransition metal
computed · instantinstant - 04
Copy symbol
Use Copy in the header to grab the symbol.
Copy writes through
navigator.clipboardand downloads use aBlob— zero network traffic. Same input plus same options always yield the same bytes.copydownloadzero-networkreproducibleok · copiedready · copiedCopied Au
shipped · ready to shipsuccess
Pro tips for everyday utilities
Reach for crypto.getRandomValues
Cryptographically random for IDs, tokens, salts. Math.random is for animation and games, not security.
Mock data with seeds
Faker-style libraries can be seeded so tests are reproducible. Embed the seed in the fixture file.
Reference cards beat memory
Cheatsheets for Vim, Git, Docker, Linux signals are faster than man pages when you’re mid-flow.
Browser APIs vary
Touch events, gamepads, and clipboard differ across vendors. Feature-detect before use.
Persist in the right place
localStorage for user preferences, sessionStorage for transient state, IndexedDB for structured data.
When to consult the table
Chemistry homework, lab, demos.
Homework
Lookup atomic mass for stoichiometry. Random values come from crypto.getRandomValues — cryptographically secure for tokens, salts, and session IDs. Math.random is deterministic enough for animations but predictable enough to be a security bug.
CSPRNG-backedLab reference
Quick electron config check. Pair with hashids, ULID, or UUID v7 when you need both random and sortable — useful for primary keys, public-facing IDs, and event log ordering without a sequence column.
reproducibleCategorization
Identify alkali metals, halogens, noble gases. Output is deterministic given the same seed, so fixtures and tests stay reproducible across CI runs and contributor machines. Embed the seed in the fixture file for full replay.
snappyProgramming
Stub data for chemistry app fixtures. Heavy work runs through useMemo so the UI stays snappy on large inputs. Same input + same options yields identical bytes — the kind of stability snapshot tests rely on.
feature-detectedQuiz prep
Memorize symbols and numbers. Storage tools persist to the right backend: localStorage for user preferences, sessionStorage for transient state, IndexedDB for structured data. Pick the right shelf and quota worries disappear.
deterministicTeaching
Project on a screen during demos. Browser feature detection: clipboard, fullscreen, gamepad, and Web Bluetooth APIs gracefully fall back when unavailable. No surprise white screens on Safari or older Firefox.
production-readyFrequently asked questions
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Tell us what you need. We ship the top requests every two weeks.