Smart Convert – Currency & Unit Conversion

Description

Smart Convert – Currency & Unit Conversion is not just another calculator, it is a complete conversion infrastructure for WordPress sites. Designed for performance and flexibility, it handles everything from simple currency exchanges to complex, non-linear physical unit conversions (like Temperature).

Whether you run a travel blog, or a technical documentation hub, this plugin ensures your visitors see accurate conversions in a format that fits your design.

🚀 My Ambition: Premium Features for Free With this initial release, my goal is to set a new standard for what a free plugin can offer. I believe advanced tools shouldn’t be locked behind a paywall. That is why Smart Convert includes enterprise-grade features usually found only in paid versions: a Custom Unit Builder, a Template Engine, Import/Export capabilities, and Automatic Geolocation—all completely free.

🌟 Key Features

💰 Advanced Currency Engine
* Rates: Supports 153 global currencies + cryptocurrencies (BTC, ETH, etc.).
* Smart Geo-Location: Automatically detects visitor IP to display their local currency (powered by ipinfo.io).
* “Spread” & Fees: Add a percentage markup (e.g., 2%) to exchange rates to simulate bank fees or retail pricing.
* Smart Rounding: Intelligently adjusts decimals (e.g., 0 decimals for JPY, 6 decimals for BTC).

📏 Comprehensive Unit Converter
* 105+ Built-in Units: Covers 14 categories including Length, Mass, Volume, Temperature, Pressure, Energy, Speed, and Data.
* Bi-Directional Custom Units: Creating a unit like “Box” (e.g., 1 Box = 12 Items). The plugin automatically generates the reverse conversion logic for you.
* Complex Math: Handles non-linear conversions (like Fahrenheit to Celsius) with precision offset calculations.

🎨 Visual & Editor Integration
* Native Gutenberg Block: Visually configure conversions (Amount, From, To, Decimals) with a live backend preview.
* Inline Toolbar Tool: Select any text in your post and convert it instantly using the rich text toolbar button.
* Interactive Tooltips: Solves the common “overflow:hidden” clipping issue using a smart portal strategy to display rates on hover.
* Template System: Design your output using placeholders like {FROM}, {TO}, {RATE}, and {DATE}.

⚙️ Performance & Workflow
* Zero Database Bloat: Uses robust Object Caching and Transients.
* Import/Export: Transfer your custom templates and custom units between sites via JSON.
* Privacy First: External connections are disabled by default until explicit consent is given via the Onboarding Wizard.

🌍 Internationalization & Translations

Smart Convert – Currency & Unit Conversion is fully localized and ready for global audiences. The plugin is translated into the following languages:

  • English
  • Spanish (Español)
  • Japanese (日本語)
  • German (Deutsch)
  • French (Français)
  • Russian (Русский)
  • Brazilian Portuguese (Português do Brasil)
  • Italian (Italiano)
  • Czech (Čeština)
  • Dutch (Nederlands)
  • Turkish (Türkçe)
  • Polish (Polski)
  • Indonesian (Bahasa Indonesia)

⚖️ Privacy & External Services Disclosure

To provide up-to-date exchange rates and geolocation features, this plugin may connect to selected third-party services.
No data is sent without your explicit consent via the settings page.

  1. Currency & Unit Data (Google Sheets via Proxy)

    • Service: Downloads conversion rates from public datasets.
    • Mechanism: Requests are routed through a static redirect wrapper on petrnovak.cz to ensure link stability.
    • Data Sent: Your server’s IP address (standard HTTP request). No visitor data is sent.
    • Policy: Google Privacy Policy
    • Proxy Policy: PetrNovak.cz Privacy Policy
  2. Geolocation (IPinfo.io)

    • Service: Used only if “Auto-detect currency from IP” is enabled in settings.
    • Mechanism: Sends the visitor’s IP address to IPinfo.io to determine their country code (e.g., “US”).
    • Data Sent: Visitor IP Address.
    • Policy: IPinfo Privacy Policy

Screenshots

  • General Settings: Configure update intervals, number formatting, and global exchange rate markups.
  • Template Manager: Manage default settings or export and import custom display formats via JSON.
  • Live Rates Dashboard: Monitor active exchange rates and their last update times in a clear table.
  • Custom Unit Builder: Create bidirectional custom units with equation previews (e.g., Pallet to Boxes).
  • Conversion Modal: Easily insert conversions with a smart popup that handles amounts, currencies, and formats.
  • Interactive Tooltips: Hover over a conversion to see the exact rate, timestamp, and markup details.

Blocks

This plugin provides 1 block.

  • Convert

Installation

  1. Upload the plugin files to the /wp-content/plugins/smart-convert-currency-unit-conversion directory, or install the plugin through the WordPress plugins screen.
  2. Activate the plugin through the ‘Plugins’ screen in WordPress.
  3. Onboarding: You will be redirected to a setup wizard.
    Click “Connect & Initialize” to download the latest rates and unit definitions.
  4. Navigate to Settings Smart Convert – Currency & Unit Conversion to configure your default currency and display preferences.

FAQ

Can I add my own units (e.g., “Pallets” to “Kilograms”)?

Yes!
Go to the Units tab and scroll to “Add Custom Unit”. You can define a name, symbol, and conversion factor.
The plugin handles the math for both directions automatically.

How does the Gutenberg Inline Tool work?

Highlight any number in your text editor (e.g., “100”), click the “Money/Convert” icon in the toolbar, and a popup will appear letting you choose the target currency or unit.

Does this plugin slow down my site?

No. Exchange rates are cached in your database (transients) and updated only once daily via WP-Cron.
The frontend shortcode uses these cached values, so no external API calls happen when a visitor loads your page.

Can I use this for Cryptocurrencies?

Yes. The plugin supports major crypto assets like Bitcoin (BTC) and Ethereum (ETH).
It also includes logic to handle high-precision decimals (up to 6 places) for small crypto amounts.

What are the Shortcode Macros/Placeholders?

When creating a custom output template, you can use:
* {FROM} – The source amount with symbol (e.g., $10)
* {TO} – The converted amount with symbol (e.g., €8.50)
* {RATE} – The exchange rate used (e.g., 0.85)
* {DATE} – The date the rate was last updated
* {RATE_INFO} – A formatted string showing rate + spread details (ideal for tooltips)

Reviews

There are no reviews for this plugin.

Contributors & Developers

“Smart Convert – Currency & Unit Conversion” is open source software. The following people have contributed to this plugin.

Contributors

“Smart Convert – Currency & Unit Conversion” has been translated into 1 locale. Thank you to the translators for their contributions.

Translate “Smart Convert – Currency & Unit Conversion” into your language.

Interested in development?

Browse the code, check out the SVN repository, or subscribe to the development log by RSS.

Changelog

1.0.2

  • Updated: Translations were updated.

1.0.1

  • Improved: Added translator comments to clarify string context for localization.

1.0.0

  • Initial release.
  • Added: 153 Currencies & 105 Physical Units.
  • Added: Native Gutenberg Block & Inline Toolbar integration.
  • Added: Custom Unit Builder with Import/Export.
  • Added: Template Manager for custom output formatting.
  • Added: Geolocation (IP-to-Currency) support via IPinfo.io.
  • Added: “Spread” feature for exchange rate markup.
  • Security: Implemented strict nonce checks and capability validation on all AJAX endpoints.
  • Performance: Implemented Object Caching for rate lookups.