Free AI & productivity toolkit,
100% in your browser
Count tokens, estimate API cost, build prompts, decode JWT, calculate loans, generate QR codes, run a classroom timer — no signup, no data leaves your device.
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🤖 AI / LLM
Token, cost, prompts, model comparison — daily LLM workflows
Token Counter
Accurate token count for ChatGPT, Claude, Gemini, Llama. Live input cost.
API Cost Calculator
Estimate monthly/yearly LLM API spend. Compare which model is cheapest.
Prompt Builder
Compose well-structured prompts. 6 templates for common tasks.
Markdown Preview
Render markdown live — paste ChatGPT/Claude output. GFM, tables, code blocks.
AI Model Comparison
GPT-5, Claude 4.7, Gemini 2.5, Llama 4, DeepSeek — context, pricing, modality (2026).
Text Diff
Paste 2 texts → highlight diffs at word/line/char level. Great for diffing AI outputs.
JSON Schema Generator
Generate JSON Schema (Draft-07) from a sample — for LLM structured output and API validation.
Image to Base64 Encoder
Drop image → base64 string. Includes data: URI prefix ready for Claude / GPT-4V / Gemini vision APIs.
📦 Data & API
JSON, YAML, CSV, JWT, UUID, JSONPath, cron, timestamp — debug & parse
JWT Decoder
Decode JWT tokens — header, payload, claims with readable timestamps.
JSON Formatter
Format / minify / validate JSON. Sort keys A-Z, custom indent, Ctrl+Enter shortcut.
UUID / Hash / Base64 / URL
Bundle: UUID v4, SHA-256/512 hash, Base64 (URL-safe), URL encode.
JSONPath Tester
Test JSONPath queries against JSON samples. Pick data from API responses, debug structured output. Recursive descent + filters.
Number Base Converter
Convert between bases 2-36 + ASCII codes. BigInt support. Useful for bitwise debugging, CS101, memory dumps.
Working Days Calculator
Count working days between 2 dates — exclude weekends + VN/Indonesia 2026 holidays (Lunar NY, Independence Day, Idul Fitri…).
CSV Diff
Compare 2 CSV files by key column. Detects added/removed/changed rows (which cell changed, from what to what).
Mock Data Generator
Generate fake data — names, emails, phones, addresses, products. 10 locales (VN/ID/JP/KR…), JSON/CSV/SQL output.
JWT Builder (HS256)
Build & sign JWT with HMAC-SHA256 via Web Crypto API. Quick claim helpers (iat, exp). For test/dev API auth.
URL Parser & Builder
Split a URL into protocol/host/path/query/hash. Edit each query param and rebuild a clean URL.
JSON to TypeScript
Generate TypeScript interfaces from JSON samples. For API responses, LLM structured output, mock data.
World Time Zone Converter
Convert time between world cities. Auto-handles DST, shows working hours, supports 22 popular timezones.
HTTP Status Code Reference
Look up HTTP status codes 1xx-5xx. Search by number or name, click to copy. Useful for debugging APIs.
Unix Timestamp Converter
Convert Unix timestamp ↔ date. Auto-detects seconds/ms, shows local + UTC + ISO + relative time.
JSON ↔ CSV Converter
Convert JSON arrays to CSV and back. Custom delimiter, flatten nested objects.
Cron Expression Explainer
Read cron expressions in plain English + next 5 run times. For Linux cron, GitHub Actions, AWS EventBridge.
JSON ↔ YAML
Convert between JSON and YAML — auto-conversion as you type, flow style supported.
Code Diff
Side-by-side code diff.
📝 Text & Markdown
Slug, case, regex, count, sort, lorem, MD table/TOC, SQL — text utilities
Regex Tester
Test regex live with match highlighting. 7 ready presets including Vietnamese.
Remove Vietnamese diacritics
Strip diacritics for slugs, filenames, usernames, identifiers. Optional đ → d.
URL Slug Generator
Title → SEO-clean URL slug. Strip diacritics, lowercase, custom separator.
Char / Word / Line Counter
Real-time char/word/line/paragraph count + SEO meta (60/160) and tweet (280) meters.
Password Generator
Cryptographically secure random passwords with entropy meter, custom char classes.
Text Case Converter
10 cases: UPPER, lower, Title, camelCase, snake_case, kebab-case, CONSTANT_CASE...
Lorem Ipsum (incl. Vietnamese)
Generate placeholder text — Latin / Vietnamese / Hacker speak. Optional <p> wrap.
Sort / Dedupe / Shuffle
A-Z, numeric, reverse, shuffle, dedupe — Vietnamese-aware.
Markdown TOC Generator
Generate a Table of Contents from markdown. GitHub-compatible anchor links. Strip diacritics, numbered, checklist.
Markdown Table Builder
Visual editor for markdown tables (GFM). Add/remove rows/cols, alignment, pretty mode balances widths.
SQL Formatter
Pretty-print SQL across 13 dialects (MySQL, PostgreSQL, BigQuery, Snowflake, MS SQL, Oracle…). UPPERCASE keywords.
HTML Entities Encode/Decode
Encode/Decode special characters to HTML entities (< & ©...). Reference table included.
Markdown → HTML Export
Convert Markdown to standalone HTML for blog publishing, email, or WordPress. 3 CSS themes (GitHub, clean, none) + dark mode + .html download.
🎨 CSS & Design
Color, gradient, shadow, animation, grid, clip-path — visual builders
Color Picker
Pick HEX/RGB/HSL, RGB sliders, 12 presets, nearest Tailwind name.
Tailwind ↔ CSS Converter
Convert between Tailwind utility classes and vanilla CSS. ~200 utilities (spacing, color, flex, grid…). Helps migration.
SVG to React/JSX
Convert SVG to React component. camelCase attrs, currentColor, TypeScript types, size/color props.
CSS Animation Builder
Visual builder for CSS animations. 10 presets (fadeIn, bounce, pulse, spin, shake…). Tweak duration, easing, iteration.
CSS Filter Builder
Visual builder for CSS filters — blur, brightness, sepia, hue-rotate, drop-shadow. 8 presets (Vintage, Polaroid, Noir…).
Color Palette Generator
Generate harmonious palettes from a base color (HSL theory). 6 schemes: Monochromatic, Analogous, Complementary, Triadic… + 10 shades.
CSS Grid Layout Generator
Visual builder for CSS Grid. 6 presets (Holy Grail, Magazine, Auto-fit…). Live preview + copy CSS.
CSS Border Radius Generator
Visual builder for border-radius — uniform, per-corner, or organic blob. 8 presets, ready-to-copy CSS.
Box Shadow Generator
Visual builder for CSS box-shadow — multi-layer, inset, opacity. 8 presets (Material, Neumorphic, Glow…).
CSS Gradient Generator
Visual builder for linear/radial/conic gradients. 8 beautiful presets, multi-color stops, ready-to-copy CSS.
WCAG Color Contrast Checker
Check contrast ratio between 2 colors against WCAG 2.1. AA/AAA results for normal + large text with live preview.
CSS Unit Converter
Convert between px / rem / em / pt / % / vw / vh. Adjustable base font-size and viewport.
CSS Clip-path Generator
12 shape presets (triangle, star, hexagon, speech bubble…) plus editable polygon points. Live preview, copy CSS.
🖼️ Image & Media
Compress, base64, placeholders, QR — 100% client-side
QR Code Generator
QR for URL, WiFi, vCard. Custom colors, download PNG.
Lorem Picsum URL Builder
Generate placeholder image URLs (Lorem Picsum) for mockups and prototypes. 6 ratios + 5 common sizes + grayscale + blur.
Image Compressor
Compress JPG/PNG/WebP, resize, change format — runs in-browser via Canvas API. Image is NOT uploaded anywhere.
🇻🇳 VN & personal utilities
Salary, tax, loans, BMI, FX — VN-specific
VN Loan & Deposit Calculator
Deposit + loan repayment, decreasing & flat rate, full amortization.
Random Number Generator
Generate random numbers with crypto-secure or seeded PRNG. 6 presets (dice, lotto, PIN…). Unique + sort options.
VN Salary Calculator
Vietnam 2026: SI 8%, HI 1.5%, UI 1%, progressive PIT, personal + dependent deductions.
Age & Date Diff Calculator
Exact age (Y/M/D), total days lived, next birthday; or diff between 2 dates.
VND Currency Converter
Convert VND ↔ 9 currencies. Editable rates, persists locally.
BMI Calculator
BMI from height + weight, 6 WHO classes, healthy weight range.
Bill Splitter & Tip Calculator
Split a bill among people with tip, VAT, and service charge. Smart rounding for easy transfer.
Discount Calculator
Final price after a discount (% or fixed), stacked extra discount + voucher, with VAT.
Number to Words
Convert numbers to Vietnamese (mốt, tư, lăm, lẻ) or English words. Up to 999 trillion. Optional "đồng" / "VND" suffix for contracts.
TDEE / BMR Calorie Calculator
BMR (Mifflin-St Jeor) and TDEE by activity level. Calorie targets for cut/maintain/bulk + macro split (protein/carbs/fat).
Compound Interest Calculator
Compound interest growth: initial principal + monthly contributions. Year-by-year table with total interest earned.
CV Extractor (AI)
AI parses CVs into a table.
SOONAI Email Writer
AI work email writer.
SOONAI Product Description
AI product copy for sellers.
👩🏫 Classroom
Timer, attendance, group maker, grading — teacher daily tools
Random Picker
Pick a random student from a list. No-repeat mode.
Group Maker
Split a class into N balanced groups, or by group size.
Classroom Timer
Fullscreen countdown for class. Color warnings + alarm.
Pomodoro Timer
25/5/15, auto-advance, sound + notification, daily pomodoro count.
Stopwatch
Stopwatch with 10ms precision, lap recording, Space/L/R shortcuts. Great for classroom, sports.
Grade Average Calculator
Weighted average, VN-scale classification, distribution chart.
Grade Convert 10 ↔ 4 ↔ Letter
10-scale (VN) ↔ 4-scale GPA (US) ↔ letter A/B/C/D/F. Bulk convert.
Classroom Attendance
Roster management, Present/Absent/Late, notes, save sessions, CSV export.
AI Quiz Generator
AI generates quizzes.
SOONAI Lesson Plan
AI lesson plan templates.
SOONFlashcards from text
Auto flashcards from material.
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