Kotak alat AI &amp; produktivitas gratis, 100% di browser Anda

🎯

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.

👨‍💻 For developers

Decode, format, convert — daily dev tools

🔐

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.

🔍

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.

🔤

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.

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.

🛤

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.

✨

CSS Animation Builder

Visual builder for CSS animations. 10 presets (fadeIn, bounce, pulse, spin, shake…). Tweak duration, easing, iteration.

📑

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.

🪞

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.

📑

CSV Diff

Compare 2 CSV files by key column. Detects added/removed/changed rows (which cell changed, from what to what).

🖼

Lorem Picsum URL Builder

Generate placeholder image URLs (Lorem Picsum) for mockups and prototypes. 6 ratios + 5 common sizes + grayscale + blur.

🎭

Mock Data Generator

Generate fake data — names, emails, phones, addresses, products. 10 locales (VN/ID/JP/KR…), JSON/CSV/SQL output.

🎚

CSS Grid Layout Generator

Visual builder for CSS Grid. 6 presets (Holy Grail, Magazine, Auto-fit…). Live preview + copy CSS.

🔏

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.

⬛

CSS Border Radius Generator

Visual builder for border-radius — uniform, per-corner, or organic blob. 8 presets, ready-to-copy CSS.

📋

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.

🌫️

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.

🦾

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.

WCAG Color Contrast Checker

Check contrast ratio between 2 colors against WCAG 2.1. AA/AAA results for normal + large text with live preview.

⏰

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.

📐

CSS Unit Converter

Convert between px / rem / em / pt / % / vw / vh. Adjustable base font-size and viewport.

🔁

JSON ↔ YAML

Convert between JSON and YAML — auto-conversion as you type, flow style supported.

🔀

Code Diff

Side-by-side code diff.

✂️

CSS Clip-path Generator

12 shape presets (triangle, star, hexagon, speech bubble…) plus editable polygon points. Live preview, copy CSS.

📤

Markdown → HTML Export

Convert Markdown to standalone HTML for blog publishing, email, or WordPress. 3 CSS themes (GitHub, clean, none) + dark mode + .html download.

👩‍🏫 For teachers

Classroom tools teachers use every day

🎲

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.

⌨️

Touch Typing Practice (Game)

Learn 10-finger touch typing via a "falling words" game + 15/30/60s WPM test. On-screen keyboard color-coded by finger; English, Vietnamese (with/without diacritics), code.

📊

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.

📚

AI Lesson Plan

AI lesson plan templates.

🎴

Flashcards from text

Auto flashcards from material.

🏢 For business

Finance, ops, marketing — VN-specific

💰

VN Loan & Deposit Calculator

Deposit + loan repayment, decreasing & flat rate, full amortization.

📱

QR Code Generator

QR for URL, WiFi, vCard. Custom colors, download PNG.

📅

Working Days Calculator

Count working days between 2 dates — exclude weekends + VN/Indonesia 2026 holidays (Lunar NY, Independence Day, Idul Fitri…).

🎲

Random Number Generator

Generate random numbers with crypto-secure or seeded PRNG. 6 presets (dice, lotto, PIN…). Unique + sort options.

🗜️

Image Compressor

Compress JPG/PNG/WebP, resize, change format — runs in-browser via Canvas API. Image is NOT uploaded anywhere.

🌍

World Time Zone Converter

Convert time between world cities. Auto-handles DST, shows working hours, supports 22 popular timezones.

📄

Word (.docx) → Excel

Extract tables from Word .docx files, export styled .xlsx. Optional URL stripping, fill-down for merged columns. Runs in-browser — file is never uploaded.

📊

Excel (.xlsx) → Word

Each sheet becomes a Word table — bold header, cell borders, auto orientation by column count. Runs in-browser — file is never uploaded.

📝

Markdown → Word (.docx)

Markdown → Word .docx preserving headings, tables, code blocks, lists, links, bold/italic. Real hyperlinks, real numbering. In-browser, never uploaded.

📄

Markdown → PDF

Markdown → PDF via the browser print engine: selectable text, clickable links, small file size. 3 themes: GitHub / Clean / Newspaper. A4/Letter, custom margins + font size.