📖 Complete User Manual

⚡ TOOLKIT PRO

Complete breakdown of every tool — Calculator, Chess, and Currency Converter. Every feature, every button, every setting — explained in detail in one place.

📋 Table of Contents
ToolKit Pro is a free, browser-based web application that brings three powerful tools to one place: an unlimited-precision calculator, a full-featured chess game with AI, and a currency converter supporting 160+ currencies with live rates.

No app installation needed. No ads to distract you from work. Just open your browser and get started. Pure HTML, CSS, and JavaScript — no React, no Vue, no complex frameworks. Works on desktop, tablet, and mobile. Works offline too (with fallbacks).
🌐
Zero Installation Policy
No downloads, no setup, no permission requests

The biggest advantage of ToolKit Pro — simply open toolkitpro.co.in and start working immediately. Works on mobile browsers, desktop, tablets. Android, iOS, Windows, Mac — everything supported. Guest mode lets you use all tools without any account. Want to create an account? Completely free and requires only an email.

Your data syncs across devices when you're logged in. Settings, preferences, everything is saved securely.

🔐
ToolKit Pro's account system is based on Supabase — a secure, open-source backend. Creating an account is optional. All tools work without login. But if you want to save your preferences, customize your avatar, and sync across devices, create an account.
📧
Email / Password Login
Standard account creation

On the login page, click the "Sign Up" tab. Enter your Full Name, Email, and a minimum 6-character Password. After submitting, you'll receive a verification email. Click the link to verify your account and you're done.

Forgot your password? Click the "Forgot password?" link on the login form, enter your registered email, and you'll get a reset link directly in your inbox.

🚀
Guest Mode
Use the app without any account

On the login page, there's a "Continue as Guest" button. Click it and the app opens immediately. You can use the Calculator, Chess, and Currency Converter without restrictions.

Guest mode has only one limitation: profile settings don't save and you can't customize your avatar or name. Everything else works exactly the same.

💡 In guest mode, Calculator history still saves during your session. It only clears when you refresh the page.
🔑
Password Recovery Flow
Step-by-step reset process

Follow these exact steps if you need to reset your password:

1On the login page, click the "Forgot password?" link
2A modal will open — enter your registered email address
3A reset link will arrive in your inbox (check spam folder if you don't see it)
4Click the link in the email — the new password setup screen appears
5Set your new password and login
🧮
The Calculator in ToolKit Pro is not just a standard calculator. It uses the Big.js library which provides unlimited decimal precision. This means: no matter how large or small the number, you get the exact answer — no rounding errors, no unexpected scientific notation.
🔢
Basic Mode — Every Button Explained
4-column standard calculator layout

In Basic mode, the calculator is arranged in 4 columns — exactly like a standard calculator. At the top is a display area split into two parts: the top line shows the expression you're entering (like "125 × 48 +"), and the bottom line shows the current or final result in bright cyan.

C (Clear)Clears everything — both the current expression and result. Fresh start.
⌫ (Backspace)Deletes the last entered character. Made a typo? Delete it one character at a time.
± (Sign)Toggles the sign of the current number — positive to negative or vice versa.
% (Percent)Divides the number by 100. 150 % = 1.5. Useful for calculating discounts.
÷ × − +Standard arithmetic operators. Tap with your finger or type from keyboard.
. (Decimal)Adds a decimal point. Only one decimal point allowed per expression.
= (Equals)Evaluates the expression and shows the answer. The result appears with a cyan glow.
0–9Number buttons. Type directly from your keyboard too.
📺
Display Area — In Detail
Expression line + Result line

The calculator display has two parts. The top line (expression line) shows your current formula — like 125 × 48 +. The bottom line (result line) shows the calculated result so far — constantly updating as you type.

You can click directly on the display and manually edit any number. This is a unique feature — edit the expression or modify numbers directly without deleting and retyping.

  • Live preview: The result updates before you press equals
  • Scroll support: If the result is very long, the display scrolls horizontally
  • Word wrap: For large numbers, text wraps to multiple lines
  • Mode badge: A BASIC or SCI badge appears in the corner showing your current mode
🔬
Scientific Mode — Advanced Functions
5-column layout with trigonometry, logarithms, and more

Switch to Scientific mode using the mode toggle at the top of the calculator with Basic and Sci buttons. In Sci mode, the layout becomes 5 columns and purple-colored buttons appear with advanced functions.

sin cos tanTrigonometric functions. Calculates in degrees or radians based on your current angle mode.
sin⁻¹ cos⁻¹ tan⁻¹Inverse trigonometric functions (arcsin, arccos, arctan). Enter a value and get the angle.
logCommon logarithm (base 10). log(100) = 2, log(1000) = 3.
lnNatural logarithm (base e). ln(e) = 1, ln(1) = 0.
Square root. Get precise results thanks to the Big.js engine — no rounding.
Square a number — multiply it by itself.
Power/exponent function. Enter x, press xʸ, enter y, then press equals.
1/xReciprocal — divides 1 by the number. 1/4 = 0.25.
πPi constant — 3.14159265358979... in full precision.
eEuler's number — 2.71828182845904..., the base of natural logarithm.
( )Parentheses — group complex expressions. (3+4)×2 = 14.
EXPScientific notation input — 2 EXP 10 means 2×10¹⁰.
DEG / RADToggle angle mode — calculate trigonometric functions in Degrees or Radians.
🎯 Pro tip: In DEG mode, sin(90) = 1. In RAD mode, sin(π/2) = 1. Physics problems typically use RAD mode.
📜
History Panel
Remembers all your calculations

On the right side of the calculator (visible on desktop, collapses on mobile) is a History panel. Every calculation you perform is saved here — the expression and its result. This makes it easy to recall previous calculations or check what you calculated earlier.

Click any history item and that calculation returns to the display — continue from there or start a new calculation with the result.

  • Session-based storage: History is saved for the current session
  • Click to recall: Click any history item to bring it back into the calculator
  • Clear all button: Red "Clear" button deletes all history at once
  • Scrollable list: No matter how many calculations — the list scrolls
  • Expression + result: Both are stored — expression on top, result below in cyan
⚙️
Big.js Precision Engine
Why this calculator is different from others

JavaScript's default number system (IEEE 754 floating point) produces small errors. For example: 0.1 + 0.2 in JavaScript gives 0.30000000000000004. ToolKit Pro uses Big.js to eliminate this problem completely.

Big.js performs arbitrary precision arithmetic — meaning no matter how large or small a number, you get the exact answer. No scientific notation surprises, no unexpected rounding.

Float Fix0.1 + 0.2 = 0.3 exactly, not 0.30000000000000004
Large Numbers999999999999999 + 1 = 1000000000000000 — no 1e15 notation
Small Decimals0.000000001 × 3 = 0.000000003 — full precision maintained
Division1 ÷ 3 = 0.3333333...20 digits — configurable precision
This is the reason ToolKit Pro was created — "phone calculators were switching to scientific notation on large numbers". Big.js solved this permanently.
♟️
The Chess game in ToolKit Pro is a full-featured chess application. Play against an AI opponent or in 2-player mode on the same device. Custom board design, coordinates, move validation, special moves — everything a chess enthusiast needs.
🤖
Game Modes
vs AI or vs Friend

At the top of the Chess panel are two mode buttons:

🤖 VS AI 👥 2 PLAYER
vs AI Mode You play White pieces, AI plays Black. An animated "thinking" indicator shows while AI calculates its move. AI responds automatically after thinking.
2 Player Mode Two people on the same device can play. Turn-by-turn gameplay — White's turn, then Black's turn. Pass the phone or keyboard between players. No online multiplayer.
🧠
AI Difficulty Levels
Easy · Medium · Hard

In vs AI mode, the sidebar has three difficulty buttons. You can change difficulty in real-time — even during the game.

Easy For beginners. AI makes random or suboptimal moves. Start here if you're learning chess. The AI misses basic tactics and makes blunders.
Medium Intermediate challenge. AI understands basic tactics — forks, pins, simple combinations. Won't give away pieces freely. But struggles with complex positional play.
Hard For experienced players. AI searches deeper, thinks several moves ahead. Plays tactical combinations accurately. A real challenge.
⚠️ In Hard mode, the AI might take a bit longer to move — it's normal. The AI is doing deep calculations.
🎯
Board — Visual Indicators
Every color has a meaning

The board shows different colors in different situations. Understanding these visual cues is important:

Cyan HighlightThe piece you selected — highlighted with bright cyan glow.
Dark DotsValid moves for the selected piece — small dark dots on empty squares. Ring indicators for capture moves.
Yellow/GoldLast move indicator — both the "from" and "to" squares of the last move glow yellow/gold.
Red PulseCheck indicator — when your king is in check, its square pulses red with animation.
CoordinatesBoard edges show rank labels (1–8) on the left and file labels (a–h) at the bottom — just like real chess notation.
🎮
Game Controls
New Game, Undo, Flip Board

Below the board, the sidebar has game control buttons:

New Game Cyan gradient button. Resets everything — the board, move history, captured pieces. Starts a fresh game with current difficulty and mode.
Undo Undoes the last move. In vs AI mode, one undo = your move + AI's move both reverse. In 2-player mode, only the last move reverses. Great for learning.
Flip Board Rotates the board 180 degrees — now you see from Black's perspective. In 2-player mode, flip the board after each turn like with a physical board.
⚖️
Special Moves — All Implemented
Castling, En Passant, Pawn Promotion

ToolKit Pro Chess implements all standard chess special moves. You don't trigger them manually — the board automatically allows only legal moves.

Castling Move your king 2 squares — Kingside (short) or Queenside (long) castling happens automatically. The rook moves into position too.
En Passant Chess's special pawn capture rule. If opponent's pawn advances 2 squares and your pawn is beside it, capture diagonally on your next turn.
Pawn Promotion When your pawn reaches the last rank, a promotion modal automatically appears. Choose: Queen, Rook, Bishop, or Knight.
Check / Checkmate When the king is in check, a red pulse animation and message banner appear. On checkmate, a game over message announces the winner.
Stalemate If no legal moves are available and the king is not in check — Stalemate — Draw. Game over banner appears.
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Sidebar — Player Bars, Captured Pieces, Move Log
All game information in one place

On the right side of the board (or below on mobile), the sidebar displays all game information:

  • Player bars: Separate bars for White and Black. The active player's bar glows cyan.
  • Captured pieces: Below each player are their captured pieces shown as emojis — helps track material advantage.
  • Move log: A scrollable box with all moves in algebraic notation (e.g., e4, e5, Nf3). Click any move to jump to that position.
  • Status card: Shows current game state — move number, whose turn, difficulty level.
  • Thinking indicator: In vs AI mode, three bouncing dots animate while AI thinks.
💱
The Currency Converter in ToolKit Pro supports 160+ currencies and pulls live exchange rates from a free external API. Enter your amount, select currencies, and get instant conversion.
💰
Basic Conversion — Step by Step
Convert in 3 simple steps

Using the currency converter is straightforward:

1In the Amount field, enter the number to convert — like 100, 1500, 0.5
2From the From dropdown, select your source currency (e.g., USD — US Dollar)
3From the To dropdown, select your target currency (e.g., INR — Indian Rupee)
4Press the Convert button or change any field — results update automatically
💡 The result box shows not just the converted amount — the exchange rate is also displayed. "1 USD = X INR" is clearly shown below.
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Swap Button
Instantly reverse currencies

Between the From and To currencies is a circular swap button (⇄). Click it and both currencies instantly exchange — the From currency becomes To, and vice versa.

After swapping, the conversion automatically recalculates. Useful when you want to check rates in both directions — USD→INR and INR→USD both.

  • Hover over the swap button and it rotates 180 degrees — nice animation
  • After swapping, the amount stays the same — only currencies swap
  • Perfect for checking return trip conversions
📡
Live Rates System
Real-time + Offline Fallback

When the Currency Converter page loads, it automatically fetches live rates from a free exchange rate API. These rates are stored in USD base and all conversions calculate from these rates.

Live Rates Automatically fetched on page load. If internet connection and API are available, you get real-time rates. Major currencies update daily.
Fallback Rates If the API is unavailable or internet is slow, the app uses static fallback rates hardcoded in the code. Approximate but functional.
160+ Currencies USD, EUR, GBP, INR, JPY, AED, SAR, CHF, CAD, AUD and exotic currencies — 160+ options in both dropdowns.
Precision Results follow rules: amounts ≥ 1 show 4 decimal places. Amounts < 1 (like 0.00001 BTC) show 8 decimal places. Amount formatting uses commas for readability.
Quick Rates Panel
See 40 currencies at once

Next to the main converter (or below on mobile) is a Quick Rates panel. It automatically shows all popular currency rates based on your current "From" currency in a grid layout.

At the top is a search box — type a currency code or name and results filter instantly. "EUR" or "Euro" both work.

  • Grid shows flag emoji, currency code, and rate together
  • Click any rate grid item and that currency automatically sets as "To" and conversion updates
  • 40 currencies display at once — usually no scrolling needed
  • Type in the search box and the grid live filters — matches both code and full name
🎯 The Quick Panel is the fastest way to compare rates across multiple currencies at once — perfect for travel planning.
🏳️
Flag Display System
Each currency shows its flag

In the converter, each currency displays with its country flag emoji. At the top are two boxes showing the selected currencies' large flags, codes, and full names.

When you change a currency from the dropdown, the flag box updates automatically. If a flag isn't available for a currency, a 💰 emoji is used as placeholder.

🎨
The ToolKit Pro UI is deliberately dark-first — deep blue-black background, cyan accents, clean typography. There's also a built-in Light Mode. Choose based on your preference and lighting conditions.
🌙
Dark Mode / Light Mode Toggle
Choose based on your preference

In the navigation bar is a theme toggle button (🌙 / ☀️). Click it and the entire app theme switches instantly. Light mode uses a clean white-grey palette with dark text. Perfect for daytime or bright environments.

Dark ModeDefault theme. Deep navy-black background (#080b12), cyan accents, easy on eyes in low light.
Light ModeClean white-grey palette, dark text, blue accents. Better during daytime or in bright environments.
💡 Your theme preference is automatically saved in your browser — the same theme will be active when you return.
🍞
Toast Notifications
Non-intrusive feedback messages

When something important happens — copy success, login confirmation, errors — a toast notification appears in the bottom-right corner. It auto-dismisses after 2–3 seconds. Non-intrusive and informative.

🧭
Navigation Bar
Sticky top nav — always accessible

The top navigation bar is sticky — it stays fixed at the top even while you scroll. On the left is the ⚡ TOOLKIT logo. Then come the tool tabs — Calculator, Chess, Currency Converter. On the right are theme toggle, settings, and user profile area.

Active TabThe current tool's tab is highlighted with cyan underline and color
Tab SwitchingClick a tab and the tool switches with a smooth slide animation — no page reload
Horizontal ScrollOn mobile, if the nav overflows, it scrolls horizontally — scrollbar is hidden
User AreaOn the right: avatar, username, and logout button (when logged in)
🍪
Cookie Consent Banner
Transparency

On your first visit, a cookie consent banner appears at the bottom. It informs you that the site uses Google Analytics and Google AdSense cookies. Accept to enable ads and analytics, or Decline to opt out.

Your choice is saved in localStorage — you won't see the banner again. All tools work normally regardless of your choice.