Web Utilities
Complete list of HTML Meta Tags
https://gist.github.com/lancejpollard/1978404
Htaccess Tester: Test htaccess directives before bricking your site.
http://htaccess.madewithlove.be/
Redirect Checker: Gives you low level information on the kinds of redirects a site page is going through.
https://www.redirect-checker.org/index.php
W3 Markup Validator: Great tool to make sure your pages all have legal HTML.
https://validator.w3.org/
HTML Formatter: Takes messy HTML and fixes it.
https://www.freeformatter.com/html-formatter.html
HTML Tidy: Similar to HTML Formatter. Sometimes you need another tool to do the same job.
https://htmltidy.net/
Online JSON Parser: Is that an error I see in your json? Json errors can kill javascript and other web apps.
http://json.parser.online.fr/
Javascript Beautifier: This also gives you hints about javascript coding errors.
https://beautifier.io/
XML Validator
https://codebeautify.org/xmlvalidator
ISO Lists: All the lists you need. Countries, states, timezones, whatever.
https://www.iso.org/obp/ui/#search
Calculators: Sometimes you just need one. Many different kinds of calculators here.
https://planetcalc.com/
Find Unclosed DIV and other tags:
https://www.aliciaramirez.com/closing-tags-checker/
REG-EX Tester: Useful for htaccess and other situations that need complex regular expressions.
https://www.regexpal.com/
Graphics, Galleries, Design
BX Slider: https://bxslider.com/ The easiest, fastest dev time, lowest overhead pro carousel/slider plugin there is. It just doesn't get easier than this. Supported by The Gallery module.
Unite Gallery: http://unitegallery.net/ Beautiful, full featured, many different galleries, and easy to use. Supported by The Gallery module.
Favicon Generator: I've never had a client who wasn't thrilled with their new favicon (browser tab graphic)
https://realfavicongenerator.net/
https://www.favicon.cc/
Gradient Editor by Color Zilla - create css gradients (like the top header background here.)
https://www.colorzilla.com/gradient-editor/
Color Scheme Generator: Sometimes inspiration needs a kick.
https://paletton.com/
Convert PNG to Base64: Useful for embedding icons in a module.
https://onlinepngtools.com/convert-png-to-base64
Placeholder.com: Easy to use URLs for placeholder graphics.
https://placeholder.com/ - image below: via.placeholder.com/250x65
Windows/OS Utiltiies
Greenshot: My go-to screenshot generator. I like this because it's super easy to use and has an editor that I can use for arrows, text, circles, etc...
https://getgreenshot.org/
SEO
Google Rich Results Test: Make sure your pages have the data they need.
https://search.google.com/test/rich-results
SEO One Click: The absolute best browser extension for quickly checking a web page meta and microdata.
http://www.seo-extension.com/
Schema.org is the definitive guide to microdata and includes json/ld examples for almost all situations.
https://www.schema.org
Resources
W3 Schools is where we learn how to code. HTML, CSS, JS, and everything else.
https://www.w3schools.com/
Stack Overflow: Any coding related question answered. Most questions have already been answered.
https://stackoverflow.com/questions
PHP Sandbox: Just in case you need to get some PHP working
https://sandbox.onlinephpfunctions.com/
Dummy Text (lorem ipsum) generator. Great for filler text when creating a mockup.
https://www.blindtextgenerator.com/lorem-ipsum
Security
Project Honeypot: Find out if an IP is a spammer or worse.
https://www.projecthoneypot.org/
Miva Merchant
Check out Miva Merchant if you are looking for a flexible, powerful, top shelf ecommerce platform.
The best resource for Mivascript functions and related information:
http://www.mivascript.com/
Shadows Style Guide and other documentation:
https://docs.miva.com/readytheme-shadows/#overview-style-guide
Miva Merchant API Functions: Use these in store pages and modules. Page Template code functions. Not all functions are here, sometimes you need to look in the LSK.
https://docs.miva.com/api-functions
Module API reference guide: Want to make miva modules or need info a particular feature? Here's the file. Note that it hasn't been updated for Miva 10 as of Jan 2021.
https://www.miva.com/pdf/MM_Module_API_Ref_Guide_v45.pdf
Miva Merchat Limited Source Kit (LSK) contains source code to about 80% of Miva Merchant. Invaluable if you are learning module and miva script coding in general.
https://apps.miva.com/miva-merchant-limited-source-kit.html