HTML Validator Lite - Online Check Syntax Errors
Paste HTML and detect unclosed tags, invalid nesting, and duplicate IDs. Lightweight client‑side validation.
UD5 Toolkit
Check & validate your SQL queries instantly online. Supports multiple dialects patterns.
Enter SQL and click Validate
Paste HTML and detect unclosed tags, invalid nesting, and duplicate IDs. Lightweight client‑side validation.
Quickly test SQL JOIN syntax (INNER, LEFT, RIGHT, FULL) with a sample database schema. Check logic and see conceptual result set without a real DB. Local only.
Validate YAML syntax with line‑by‑line error messages. Also format messy YAML into clean, indented output. All in your browser.
Check if a word or phrase is a palindrome (reads same forward and backward). Live validation and fun facts.
Enter any phrase and instantly see if it's a palindrome, ignoring spaces and punctuation. Fun for word nerds.
Paste your sitemap XML and check for missing namespaces, invalid URLs, or size limit violations. Keep your SEO healthy.
Paste a test card number to verify Luhn algorithm, identify issuer (Visa, MC), and check length. No real data.
Take a perfectly fine phrase and insert realistic-looking typos. For pranks or testing spell‑checkers.
Build 'I feel... when... because...' statements interactively. Improve communication in relationships. Local only.
Paste tab‑separated or CSV data and instantly get a beautifully aligned Markdown table. Essential for documentation.
Paste HTML snippet and see calculated tab order. Identify missing focusable elements. A11y helper.
Turn any sentence into mocking SpongeBob‑style text. Choose intensity. Copy and paste into chats. Pure client.
Enter products with different prices and weights/volumes. The tool ranks them by best value per unit. Save money effortlessly.
Calculate absolute error, relative error, and percent error between experimental and theoretical values. For science students. Instant local math.
Enter adjusted gross score, course rating, and slope to calculate the round's handicap differential. Track your index.
Enter recent scores, course rating, and slope to estimate a golf handicap index. Simple formula for unofficial tracking. Local only.
Generate a camping checklist based on trip style (car, backpacking, glamping). Check off items. Fully local.
Select symptoms to see possible vitamin links and food sources. Not medical advice, educational.
Enter notes or chords on a virtual fretboard and generate ASCII tablature. Quick way to share musical ideas.
Use the new `commandfor` and `command` attributes to invoke actions on other elements without JavaScript. See the spec live.
Start with a word and find synonyms, then synonyms of synonyms. Build a chain and explore language. Local thesaurus.
Translate English text to Pig Latin and decode back. A classic word game for all ages. Rules-based translation runs in your browser.
Enter your weight, height, boot sole length, and skier type to see the recommended DIN release setting.
Compute the error function and complementary error function for any real x. Quick and precise. Pure frontend math.
Generate a comprehensive first aid kit list for home, car, or hiking. Check off what you have.
Shows a random short word and displays animated ASL fingerspelling letters. Type what you see. Improve receptive skills.
Two players type the same text on the same keyboard (WASD vs Arrow zones) and race to finish first. Fun classroom game.
Generate a random, funny or serious company slogan for your startup idea. Brainstorming helper. All local.
Convert any text into its binary representation (8-bit per character). See the raw bits. Suitable for learning computer fundamentals. All local.
Find complementary, triadic, analogous, and split-complementary color combinations. Interactive color wheel. Essential for UI design.