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).
Image to Base64 Encoder
Drop image → base64 string. Includes data: URI prefix ready for Claude / GPT-4V / Gemini vision APIs.
🧑💻 Programming / Dev
JSON, JWT, regex, SQL, cURL, CIDR, Mermaid, commits — daily dev toolkit
JWT Decoder
Decode JWT tokens — header, payload, claims with readable timestamps.
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.
JSON Formatter
Format / minify / validate JSON. Sort keys A-Z, custom indent, Ctrl+Enter shortcut.
Regex Tester
Test regex live with match highlighting. 7 ready presets including Vietnamese.
UUID / Hash / Base64 / URL
Bundle: UUID v4, SHA-256/512 hash, Base64 (URL-safe), URL encode.
Tailwind ↔ CSS Converter
Convert between Tailwind utility classes and vanilla CSS. ~200 utilities (spacing, color, flex, grid…). Helps migration.
JSONPath Tester
Test JSONPath queries against JSON samples. Pick data from API responses, debug structured output. Recursive descent + filters.
SVG to React/JSX
Convert SVG to React component. camelCase attrs, currentColor, TypeScript types, size/color props.
Markdown TOC Generator
Generate a Table of Contents from markdown. GitHub-compatible anchor links. Strip diacritics, numbered, checklist.
Number Base Converter
Convert between bases 2-36 + ASCII codes. BigInt support. Useful for bitwise debugging, CS101, memory dumps.
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.
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.
JSON to TypeScript
Generate TypeScript interfaces from JSON samples. For API responses, LLM structured output, mock data.
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.
HTML Entities Encode/Decode
Encode/Decode special characters to HTML entities (< & ©...). Reference table included.
JSON ↔ YAML
Convert between JSON and YAML — auto-conversion as you type, flow style supported.
cURL ↔ fetch / axios
Convert cURL commands to fetch/axios JavaScript and back. Supports method, headers, body, query, multipart.
Regex Explainer
Break a regex into tokens and explain each — anchors, groups, quantifiers, classes. Complements Regex Tester.
CIDR / Subnet Calculator
Calculate subnet mask, network/broadcast, host range, IP count from CIDR (e.g. 10.0.0.0/24). Full IPv4 + subnetting.
Mermaid Live Editor
Mermaid editor with real-time preview — flowchart, sequence, ER, gantt, class. 6 templates, SVG/PNG export.
Conventional Commit Builder
Build Conventional Commits-compliant messages. Pick type (feat/fix/...), scope, breaking change. Preview SemVer impact.
SemVer Bump / Compare / Range
Bump versions per Semantic Versioning 2.0.0 (major/minor/patch/prerelease). Compare versions, test ranges ^/~/>=/<.
JSON Diff (structural)
Compare two JSON values structurally (key/value), independent of formatting. Shows added/removed/changed keys with JSONPath.
HMAC Signer / Webhook Verifier
Compute HMAC-SHA1/256/384/512 via Web Crypto. Presets for GitHub, Stripe, Slack — verify webhook signatures locally.
OpenAPI / Swagger Viewer
Paste OpenAPI 3.x (YAML/JSON) → view endpoints with params, body, responses, schemas. Filter by path/tag.
TypeScript → Zod Schema
Convert TS interface/type/enum to Zod runtime-validation schema. Primitives, optional, array, union, literal, enum.
.env Masker
Mask .env values before sharing — 4 modes, allowlist/blocklist, .env.example generator. Avoid secret leaks in shared logs.
YAML / JSON5 Validator
Validate YAML or JSON5 (comments, trailing commas) → strict JSON output. For GitHub Actions, K8s manifests, tsconfig.
String Escape
Encode/decode strings across 7 formats: HTML, URL, JavaScript, JSON, SQL, Base64, Shell. One-click reverse.
JSON ↔ TOML
Convert JSON ↔ TOML. For Cargo.toml, pyproject.toml, Netlify config. Two-way sync as you type.
Code Diff
Side-by-side code diff.
NEWMarkdown → HTML Export
Convert Markdown to standalone HTML for blog publishing, email, or WordPress. 3 CSS themes (GitHub, clean, none) + dark mode + .html download.
📦 Data & Time
CSV diff, time zones, working days — data & calendar utilities
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).
World Time Zone Converter
Convert time between world cities. Auto-handles DST, shows working hours, supports 22 popular timezones.
📝 Text & Markdown
Slug, case, regex, count, sort, lorem, MD table/TOC, SQL — text utilities
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.
Word Frequency Counter
Count word + phrase frequencies (1/2/3-gram). VN/EN stop-words, min length. For SEO keyword density, content audit.
🎨 CSS & Design
Color, gradient, shadow, animation, grid, clip-path — visual builders
Color Picker
Pick HEX/RGB/HSL, RGB sliders, 12 presets, nearest Tailwind name.
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.
Glassmorphism Generator
Visual builder for the frosted-glass effect — blur, transparency, saturation. 4 background presets, copy CSS.
CSS Loader / Spinner Generator
8 pure-CSS loader presets (ring, dots, pulse, bars, wave, orbit, flip…). Tweak size, color, speed — copy HTML+CSS.
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.
Color Picker from Image
Drop an image and click to pick HEX/RGB/HSL. Auto-extracts dominant palette. Canvas API, no upload.
🇻🇳 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.
Roman Numerals Converter
Convert between natural numbers and Roman numerals (1-3999). Breakdown of I/V/X/L/C/D/M composition.
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.
Multiplication Table
Multiplication tables 1-20 — printable, practice mode (hide answers), quiz mode. Parents teaching kids math.
AI Quiz Generator
AI generates quizzes.
SOONAI Lesson Plan
AI lesson plan templates.
SOONFlashcards from text
Auto flashcards from material.
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