Free tools for the webmaster

What software does a webmaster uses to create a website? Here is a selection of tools and online services for every stage of the creation and management of sites.

Domain name

Informer. Infos about a domain and all the domains for a firm.
Reverse Whois Lookup. List of domains registered by an applicant. Not all domains are provided. Country level extensions are not included and even in generics, some domains may be missing.

Analysis of a website

Page Speed. By Google browser plugin running in addition to Firebug. It will scan your site to get the loading time and how you can optimize it to make it faster. The Site speed is a factor in the ranking said Google.
Web Page Test. Makes an analysis of the page whose URL is given and then conducts an audit about possible performance improvement.
Copyscape. Search sites similar to your. May be achieved also by a search on Google with a sentence from your pages between quotes.
Squish. Technical Web service, let know the host of a site among others.
Who hosts who. Type the domain and know who is the host.
What Runs. Extension to Firefox which show what power any website.
Spyonweb. To know all the sites from a same webmaster.
Hemingway. Style checker, help you to make your texts more readable.
TinEye. Finds the origin of an image. Also lets you know who copy your images.
Safe diagnostic by Google: Copy the code below and paste it in the URL bar, and replace "example.com" by the domain to verify:

https://www.google.com/safebrowsing/diagnostic?site=example.com

Checking pages and site

Validator W3C. Checks the validity of the HTML and CSS code of a web page. Check also an RSS file.
Rich snippet testing tool. Si la page inclut un microformat, teste sa validité.
Testing the speed of loading. Not on his computer but from another one.
Safe Browsing. Tool from Google to check your site against malwares. Replace mysite.com by the domain of your site.
```
https://www.google.com/safebrowsing/diagnostic?site=mysite.com   
```

Rating a website: ranking and traffic

SEO Quake. Browser extension, that adds a toolbar to display lot of useful data for ranking a website.

Keywords: advices

Google trends. What are users searching for?
Google suggest, when a request is entered in the search bar, frequently requested queries are displayed, that gives an insight on what want visitors..

Backlinks

CleverStat's Backlinks Master. Backlinks analyser. Free software to download.
Urltrends. Analysis of backlinks and external links.
Majestic SEO. Give the list of links to a page. Not all the backlinks are listed.
Majestic Compare. Evolution over time of the backlinks to your site or comparison of two sites. I do not know if the values are really valid.
Link Explorer. Provides the number and a limited list of backlinks to any site. Registering is not required.
And of course, Google Webmaster Tools provide the liste of backlinks to your site.

Links checkers

Xenu's Link Sleuth. (Windows) Link checker to download for Windows.
Link Checker. (On this site). Command link tool or with a GUI in Tiloid. Requires PHP and works on any operating système.
PHP FTP Synchronizer can also check links in a page when uploaded.

Sitemap and indexing

The best means to submit a sitemap is to include its URL into the robots.txt file.

Simple map. (PHP/ On this site) Convenient for a site edited locally and put online then. Build an XML or HTML sitemap. The XML format is standard and common to Google, Yahoo and Bing.
Firebase indexing. Let a web app indexed by Google's search engine.

Server

Server monitoring. From a browser, with a SSH tunnel (or multiple accesses). Works on a Linux server with Ruby or a Bash script.
Hummingbird. To view in real-time traffic on your site, to be installed on a hosting. Written in JavaScript and based on Node.js, it works on all systems.
Spamhaus. Provides the list of IP of spam sites.
Project Shield. A service offered for free by Google to help websites to guard against DDoS attacks.

Others

Google Shell. Using Google in command line.
Seochat. List of tools for SEO.
Follow-up of optimization. Free Web service to check optimizations.
Spider SEO. Generate meta tags with a graphical user interface. Build a report of metas and links.
RSS Tools. PHP functions to build a feed or to display RSS or Atom feeds on your pages.
The article Statistics tools for webmasters, provides more info and more link to tools.