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Google Ranking Factors - SEO Checklist

There are "over 100 SEO factors" that Google uses to rank pages in the Google search results (SERPs). What are the search engine optimization rules? Here is the speculation - educated guesses by SEO webmasters on top webmaster forums. Various confirmed and suspected Google Search Engine Optimization (SEO) Rules are listed below.

Google Ranking Factor Checklist

Updated 11-11-2005

The SEO Rules listed below are NOT listed by weight, and not by any presumed relevance - THAT exercise is left up to the reader!

Alleged POSITIVE ON-Page SEO Google Ranking Factors (38)

(Keeping in mind the converse, of course, that when violated, some of these factors immediately jump into the NEGATIVE On-Page Ranking Factors domain.)

The term "Keyword" below refers to the "Keyword Phrase", which can be one word or more. Green rows confirmed by Google patent - updated 08-26-05

Note - Patent Claim # Factor # POSITIVE ON-Page SEO Factors Brief Note
50 - keywords Google patent - Topic extraction
Hot 1 Keyword in URL First word is best, second is second best, etc.
Hot 2 Keyword in domain name Same as in page-name-with-hyphens
Keywords - Header
Hot 3 Keyword in title tag Keyword in Title tag - close to beginning Title tag 10 - 60 characters, no special characters The Florida Update EVEN penalized for this, as part of the OOP. That was absurd, but effective.
- 4 Keyword in description meta tag Shows theme - less than 200 chars. (Was part of Google Florida OOP) Google no longer relies upon this tag, but frequently uses it.
- 5 Keyword in keyword metatag Shows theme - less than 10 words. (Was part of Google Florida OOP) Every word in this tag MUST appear somewhere in the body. If not, it will be penalized for irrelevance. NO single word should appear more than twice. If not, it is considered spam. Google purportedly no longer values this tag, but others do.
Keywords - Body
- 6 Keyword density in body text 5 - 20% - (all keywords/ total words) Some report topic sensitivity - the keyword spamming threshold varies with the topic?
- 7 Individual keyword density 1 - 6% - (each keyword/ total words)
Hot 8 Keyword in H1, H2 and H3 Use H1 font style (Was part of Google Florida OOP)
- 9 Keyword font size In strong, bold, italic, etc.
- 10 Keyword proximity (for 2+ keywords) Adjacent is best
- 11 Keyword phrase order Does order in the page match order in the query? Anticipate query - match word order.
- 12 Keyword prominence (how early in page/tag) Most important at top of page, in bold, in large font
Keywords - Other
- 13 Keyword in alt text Should describe graphic - Do NOT fill with spam (Was part of Google Florida OOP - tripped a threshold - may still be in effect to some degree as a red flag, when summed with all other on-page optimizations).
- 14 Keyword in links to site pages (anchor text) Links out anchor text use keyword?
Navigation - Internal Links
Site 15 To internal pages- keywords? Link should contain keywords. The filename "linked to" should contain the keywords. Use hyphenated filenames, but not long ones.
Site 16 All internal links valid? Validate all links to all pages on site.
Site 17 Efficient - tree-like structure Two clicks to any page - no page deeper than 4 clicks
Site 18 Intra-site linking Appropriate links between lower-level pages
Navigation - Outgoing Links
55 19 To external pages- keywords? Google patent - Link only to good sites. Do not link to link farms.
56 20 Outgoing link Anchor Text Google patent - Should be on topic, descriptive
61,62 21 Link stability over time Google patent - Avoid "Link Churn"
- 22 All external links valid? Validate all links periodically.
- 23 Less than 100 links out total Google says limit to 100, but readily accepts 2-3 times that number. ref 2k
OTHER ON-Page Factors
- 24 Domain Name Class .edu seem to be given the highest status
.org sites seem to be given high status
.com sites excel in encompassing all the spam/ crud sites, resulting in the need for the highest scrutiny/ action by Google. Perhaps one would do well with the new .info domain class.
- 25 File Size Absolutely do not exceed 100K page size. Small files preferred <40K (lots of them).
- 26 Hyphens in URL Preferred method for indicating a space, where there can be no actual space One or two= excellent for separating keywords Four or more= BAD, starts to look spammy Ten = Spammer for sure, demotion probable?
6, 7, 12, 13 27 Freshness of Pages Google patent - Changes over time Newer the better - if news, retail or auction! Google likes fresh pages. So do I.
8, 9 28 Freshness - Amount of Content Change New pages - Ratio of old pages to new pages
27 29 Freshness of Links Google patent - May be good or bad
- 30 Frequency of Updates Frequent updates = frequent spidering
- 31 Page Theming Page exhibit theme? General consistency?
- 32 Keyword stemming Stem, stems, stemmed, stemmer, stemming, stemmist, stemification
- 33 Applied Semantics Synonyms, CIRCA whitepaper
- 34 LSI Latent Semantic Indexing - Speculation, no proof
- 35 URL length Keep it minimized - use somewhat less than the 2,000 characters allowed by IE - less than 100 is good, less even better
5 36 Site Size - Google likes big sites Larger sites are presumed to be better funded, better organized, better constructed, and therefore better sites. Google likes LARGE sites, for various reasons, not all positive. This has resulted in the advent of machine-generated 10,000-page spam sites - size for the sake of size.
4 37 Site Age Google patent - Old is best.
3 38 Age of page vs. age of site Age of page vs. age of other pages on site

Note: For ALL the POSITIVE On-Page factors listed above, PAGE RANK can OVERRIDE them all. So can Google-Bombing.


Alleged Negative ON-Page SEO Google Ranking Factors (24)

Note Factor # NEGATIVE ON-Page SEO Factors Brief Note
Bad 39 Text presented in graphics form only No ACTUAL body text on the page Text represented graphically is invisible to search engines.
Bad 40 Affiliate site? The Florida update went after affiliates with a vengeance - flower and travel affiliates were hit hard - cookie-cutter sites with massive inter-linking, but little unique content. Subsequent updates have also targeted affiliates.
Bad 41 Over optimization penalty (OOP) Penalty for over-compliance with well-established, accepted web optimization practices. Since the Florida update, if you simply cannot achieve top position, your only alternative to first page SERP exposure may be Google AdWords (you pay for exposure).
Bad 42 Link to a bad neighborhood Don't link to link farms, FFAs (Free For Alls) Don't forget to check the Google status of EVERYONE you link to periodically. A site may go "bad", and you can end up being penalized, even though you did nothing.
Bad 43 Redirect thru refresh metatags Don't immediately send your visitor to another page other than the one he/ she clicked on.
Bad 44 Vile language - ethnic slur Including the George Carlin 7 bad words you can't say on TV, plus the 150 or so that followed. Don't shoot yourself right straight in the foot. Also, avoid combinations of normal words, which when used together, become something else entirely - such as the word juice, and the word love.
Bad 45 Poison words "Links" in title tag, etc. Here is my list of Poison Words for Adsense. This penalty has been loosened - many of these words now appear in normal context, with no problems. But watch your step.
Bad 46 Excessive cross-linking - within the same C block (IP=xxx.xxx.CCC.xxx) If you have many sites with the same web host, prolific cross-linking can indicate more of a single entity, and less of democratic web voting. Easy to spot, easy to penalize.
Bad 47 Stealing images/ text blocks from another domain Copyright violation - Google responds strongly if you are reported. ref egol File Google DMCA
Bad 48 Keyword stuffing threshold In body, meta tags, alt text, etc. = demotion
?? 49 Keyword dilution Targeting too many unrelated keywords on a page, which would detract from theming, and reduce the importance of your REALLY important keywords.
?? 50 Page edit - can reduce consistency Google patent - Google is now switching between a "Newer" cache, and an "Older" cache, frequently drawing from BOTH at the same time. This was implemented to frustrate SEOers. Did your last edit substantially alter your keywords, or theme? Expect noticeable SERP bouncing.
6 - 7 51 Frequency of Content Change Google patent - Too frequent = bad
32, 33 52 Freshness of Anchor Text Google patent - Too frequent = bad
?? 53 Dynamic Pages Problematic - know pitfalls - shorten URLs, reduce variables, lose the session IDs
?? 54 Excessive Javascript Don't use for redirects, or hiding links
?? 55 Flash page - NOT Most (all-?) SE spiders can't read Flash content Provide an HTML alternative, or lose out.
?? 56 Use of Frames Spidering Problems with Frames - STILL
- 57 Robot exclusion "no index" tag Intentional self-exclusion
- 58 Single pixel links A red flag - one reason only - a sneaky link.
- 59 Invisible text (Google is now devaluing some pages) OK - No penalty - Google advises against this. All over the place - but nothing is ever done. (The text is the same color as the background, and hence cannot be seen by the viewer, but is visible to the search engine spiders.)
- 60 Gateway, doorway page

(I see changes here - not only does the doorway page disappear, but the main page gets pushed down, as well - this is a welcome fix.)
OK - No penalty - Google advises against this. Google used to reward these pages. Multiple entrance pages in the top ten SERPs - I see it daily. There they are at #2, with their twin at #5 - 6 months now. Reported numerous times.
- 61 Duplicate content (YOUR'S) Duplicate content (THEIR'S) below (Highjack) OK - No penalty - Google advises against this. Google picks one (usually the oldest), and shoves it to the top, and pushes the second choice down. Currently a big issue with stolen content - the thief usurps your former position with YOUR OWN content.
- 62 HTML code violations (The big G does not even use DOCTYPE declarations, required for W3C validation.) Doesn't matter - Google advises against this. Unless of course, the page is totally FUBAR. Simple HTML verification is NOT required (but advised).
- - Since the above 4 items are so controversial, I would like to add this comment: There are many things that Google would LIKE to have webmasters do, but that they simply cannot control, due to logistical considerations. Their only alternative is to foment fear and doubt by implying that any violation of their "suggestions" will result in swift and fierce demotion. (This is somewhat dated - G is getting around to fixing these things.) IN GENERAL, this works pretty well to keep webmasters in line. The fallacy of this is that even the casual observer can readily observe continuing, blatant exceptions to these official pronouncements. SPAM reports elicit no response, unless specific-case, knob-tweaking penalty imposition is authorized. There are many anecdotes about GG "taking care" of a problem. Google states that they do not provide hand-tweaked "boosts", but are silent about hand-tweaked demotions. They occur, fer shure. To believe otherwise is naive. Wouldn't YOU swat the most obnoxious flies? I would. Avoid any Google blacklist which may exist.


Alleged POSITIVE OFF-Page SEO Google Ranking Factors (43)

Note Factor # POSITIVE OFF-Page SEO Factors Brief Note
Incoming Links:
Hot 63 Page Rank Based on the Number and Quality of links to you Google link reporting continues to display just a SMALL fraction of your actual backlinks, and they are NOT just greater than PR4 - they are mixed.
- 64 Total incoming links ("backlinks") Historically, FAST counted best
No more - Yahoo (parent) broke it.

In Yahoo search, type in:

Try MSN -
Use link:www.domainname.com
- 65 Incoming links from PR4+ pages What Google used to count (report). Now, what Google reports seems almost random, frequently changing.
- 66 Acceleration of link popularity (used to be a good thing ...Martha) Google patent Link acquisition speed boost - speculative Too fast = artificial? Sandbox penalty imposed if new site?
For Each Incoming Link :
- 67 Page rank of the referring page Based on the quality of links to you
Hot 68 Anchor text of inbound link to you Contains keyword, key phrase? #1 result in SERP does NOT EVEN need to have the keyword(s) on the page, ANYWHERE!!! What does that tell you? (Enables Google-bombing - search for "miserable failure")
- 69 Age of link Google patent - Old = Good.
- 70 Frequency of change of anchor text Google patent - Not good. Why would you do that?
- 71 Popularity of referring page Popularity = desirability, respect
- 72 # of outgoing links on referrer page Fewer is better - makes yours more important
- 73 Position of link on referrer page Early in HTML is best
- 74 Keyword density on referring page For search keyword(s)
- 75 HTML title of referrer page Same subject/ theme?
28 76 Link from "Expert" site? Google patent - Big time boost (Hilltop or Condensed Hilltop) Recently reported to give a big boost !
- 7 Referrer page - Same theme From the same or related theme? BETTER
- 78 Referrer page - Different theme From different or unrelated theme? WORSE
- 79 Image map link? Problematic?
Hot 81 Site listed in DMOZ Directory? HUGE boost - it is said that Google's directory comes STRAIGHT from the DMOZ directory. You MUST get into dmoz. Be careful who you approach with the old spondulix. It is almost impossible to get into DMOZ. This site cannot get in, after waiting over 2 YEARS (28 months). Not even in the lowest, most insignificant category, "Personal Pages". I guess I just don't "measure up" to the other 20,000+ sites in this category.
- 82 DMOZ category? Theme fit category? General or geographic category? Both are possible, and acceptable.
Hot 83 Site listed in Yahoo Directory? Big boost - You can get in by paying $299 each year.
- 84 Site listed in LookSmart Directory? Boost? Another great vote for your site.
- 85 Site listed in inktomi? Use Pure Search to check your inktomi position.
- 86 Site listed in other directories (About, etc.) Directory listing boost (If other RESPECTED directories link to you, this must be positive.)
- 87 Expert site? (Hilltop or Condensed Hilltop) Large-sized site, quality incoming links
Hot 88 Site Age - Old shows stability Google patent Boost for long-established sites, new pages indexed easily The opposite of the sand box.
- 89 Site Age - Very New Boost Temporary boost for very new sites - I estimate that this boost lasts from 1 week to 3 weeks.
- 90 Site Directory - Tree Structure Influences SERPs - logical, consistent, conventional
- 91 Site Map and more site map Complete - keywords in anchor text
- 92 Site Size Previously, many pages preferred - conferred authority upon site, thus page. Bigger sites = better SERPs Now, fewer pages preferred, due to proliferation of computer-generated pages.
- 93 Site Theming Site exhibit theme? Use many related terms? Have you used a keyword suggestion tool? A thesaurus?
Page Metrics - User Behavior - Currently implemented through the Google tool bar?
34, 35 94 Page traffic Google patent - # of visitors, trend
15, 16, 21 95 Page Selection Rate - CTR Google patent - How often is a page clicked on?
36, 37 96 Time spent on page Google patent - Relatively long time = indicates relevance hit
45, 46 97 Did user Bookmark page? Google patent - Bookmark = Good
47 98 Bookmark add/ removal frequency Google patent - Recent = Good?
- 99 How they left, where they went Back button, link clicked, etc.
Page Metrics - User Behavior - Currently implemented through the Google tool bar?
34, 35 100 Site Traffic Google patent - # of visitors, increasing trend = good
- 101 Referrer Authoritative referrer?
- 102 Keyword Keyword searches used to find you
- 103 Time spent on domain Relatively long time = indicates relevance hit Add brownie points.
Domain Owner Behavior:
40 104 Domain Registration Time Google patent - Domain Expiration Date Register for 5 years, Google knows you are serious. Register for 1 year, is it a throw-away domain?
39 105 Are associated sites legitimate? Google patent - No spam, ownership, etc.


Alleged NEGATIVE OFF-Page SEO Google Ranking Factors (13)

Note Factor # NEGATIVE OFF-Page SEO Factors Brief Note
- Added Traffic Buying Have you paid a company for web traffic? It is probably low quality traffic, with a zero conversion rate. Some providers of traffic for traffic's sake may be considered "bad neighborhoods". Can Google discount your traffic (for true popularity), because they know it's mostly phony? Have you read about Traffic Power?
22, 29 106 Temporal Link Analysis In a nut shell, old links are valued, new links are not. This is intended to thwart rapid incoming link accumulation, accomplished through the tactic of link buying. Just one of the sandbox factors.
18 107 Change of Meanings Query meaning changes over time, due to current events
Bad 108 Zero links to you You MUST have at least 1 (one) incoming link (backlink) from some website somewhere, that Google is aware of, to REMAIN in the index.
Bad 109 Link-buying (Very good IF you don't get caught, but don't do it - when caught, the penalty isn't worth it.) Google patent - Google hates link-buying, because it corrupts their PR model in the worst way possible. 1. Does your page have links it really doesn't merit? 2. Did you get tons of links in a short time period? 3. Do you have links from high-PR, unrelated sites?
41, 42 110 Prior Site Ranking Google patent - High = Good
Bad 111 Cloaking Google promises to Ban! (Presenting one webpage to the search engine spider, and another webpage to everybody else.)
?? 112 Links from bad neighborhoods, affiliates Google says that incoming links from bad sites can't hurt you, because you can't control them. Ideally, this would be true. However, some speculate otherwise, esp., when other associated factors are thrown into the mix, such as web rings.
Bad 113 Penalties - resulting from Domain Hijacking (work with Google to fix) Should result in IMPRISONMENT, forthwith! Grand Theft, mandatory minimum sentence. The criminal COPYS your entire website, and HOSTS it elsewhere, with . . . a few changes.
- 114 Penalty - Google TOS violation WMG is the worst offender - gobbles up tons of Google server time by nervous Nellie webmasters. Google even mentions them by name. I think that Google will spank you when you cross the threshold, of say, 100 queries per day for the same term, from the same IP. Google can block your IP. Get a Google API.
?? 115 Server Reliability - S/B >99.9% What is your uptime? Ever notice a daily time when your server is unavailable, like about 1:30 AM? How diligent must Googlebot be? This is the worst reason to get dropped - you just aren't there! An ISP maintenance interruption can cause delisting..
- 116 No more room Pages being dropped from large sites The 232 problem - Google has hit the 4.3 Gigabyte address space wall. Bull! Google now has over 8 Gigs of indexed pages. Thousands of pages are disappearing from various huge websites, but I think that it is G just cleaning house, by dumping computer-generated pages.
Hot 117 Rank Manipulation by Competitor Attack
(1. Content theft causing you to get a duplicate content penalty, even though your content is the original - Google has problems tracking original authorship.)
Latest - Site - Wide Link Attack
302 Redirect Attack
Hijacker Attack
Impossible by Google definition (except for a few nasty tricks, like making your competition appear to be link spammers) Ideally, there SHOULD be nothing that your competition can do to directly hurt your rankings. However, an astute observer noticed that Google changed their website to read : Old verbiage = "There is nothing a competitor can do to harm your ranking ..." New verbiage = "There is ALMOST nothing a competitor can do ..." An obvious concession that Google thinks that at least some dirty tricks work! Of course, there will always be new ones!
- 118 Bouncing Ball Algorithm At least 2, and often 3 identifiable Google Search Algos are currently in use, alternating pseudo-randomly through the data centers.
GOOD LUCK NOW on trying to figure things out! IN ADDITION, some the above factors are being "tweaked" daily. Not only are the "weights" of the factors changed, but the formula itself changes. Change is the only constant.
An algo change can boost or demote your site. I put this in the negative factors section, because your position is never secure, unless of course, you are huge (PR=7 or greater). If you simply cannot achieve top position, your only alternative to first page SERP exposure may be Google AdWords (you pay for exposure).
Today, I searched for an extremely competitive "2-word term", and I found that NOT ONE of the top ten Google SERPs had even one of the words on the page.
Today's theory - when it doesn't matter, anybody can get #1 in a second, if they know the on-page rules. BUT, after a certain "commercial competitive level", the "semantic analysis" algo kicks in, and less becomes more. The keyword density rules are flipped upon their noggins. I think that we are witnessing the evolution of search engine anti-seo sophistication, right before our very eyes. Fun stuff.


Recent Updates -
What's the Buzz?
"multiple small updates"

2005 -
Novem. 5 - Jagger 3 Update

Nov.10 all done - settling out..

October 26 - Jagger 2 Update
More SERPs churning - OLD is highly valued.

October 17 - Jagger 1 Update
Recent Links, Recent Sites = SERP Turmoil
Google has declared war on phony links
Devaluation of reciprocal from unrelated-subject pages
Devaluation of links from "link houses"
Devaluation of purchased links
Big allinanchor changes
Large companies thrust to the top of the SERPs
Sandbox update
Lowering of sandbox threshold - re-sandboxing
Too fast link accumulation - links acquired too quickly
Deeper sandbox (longer - over 6 months)
Some suggest that one's site really had to be online before January 2004,
in order to avoid most ramifications of the sandbox.

Brief Google Algorithm Update List -
2005 - Sept. - the "False" Update (Sep.22 - Big update, many changes)
2005 - May - Bourbon Update
2005 - Febr.- Allegra Update - Feb.17, 2005, Some sites released from the sandbox, but many remain.
2004 - Feb.- Brandy Update
2004 - Jan.- Austin Update
2003 - Nov.- Florida Update
2003 - June - Esmeralda Update
2003 - May - Dominic Update
2003 - Apr. - Cassandra Update
2003 - Mar. - Boston Update

The Google Sandbox - The Single-Biggest SEO Ranking Factor for New Sites

Google is clearly fighting spam by sacrificing SERP newness for higher SERP quality.

March 2004

THE GOOGLE SANDBOX In March 2004, Google implemented a new filter, now referred to as "The Sandbox". This new "effect" took months to notice and quantify.

If you subscribe to the spam reduction theory, Google's thinking was, NO NEW SITES get good ranking, until they prove themselves. Spammers generate thousands of new pages daily, along with millions of new links to go with them.

Google WITHHOLDS high ranking ability on new (recently appearing?) sites, by deprecating the new links, for 2-4 months. If the domain and backlinks have existed for a certain length of time (4 months?), then you are OK, and escape from the sandbox.

This penalty is new-site based. Long-standing sites have no trouble ranking new pages.

Over time, the newly generated links are given weight, and eventually the sandbox effect is lifted.

Two methods are currently being used to get around the Sandbox penalty for new sites.

One method is to join the Google Adwords or Adsense program, in which case your pages get spidered in MINUTES. Your site will be checked initially with an algo or human "smell test". If you smell good, you're in. Good rankings will follow (provided of course, that you have good on-page SEO, and a few good backlinks).

I speculate that if you are a Google partner ("approved"), then you are not going to be penalized, unless you subsequently "go bad".

The second method is to buy an old domain, just for it's longevity, and old backlinks. Many have bought up old domain names for this purpose. This may work right now, but the rules will soon change again. They always do. Good luck!

Notes to the Above 118 Google Ranking Factors:
   1    I have tried to summarize the best opinions of many webmaster forum posters.
2 There are no published rules - this is my continuingly changing compilation of SEO chatter.
3 If your keywords are Rare and Unique, then Page Rank doesn't matter.
4 If your keywords are very Competitive, then Page Rank becomes very important.
5 The fewer incoming links that you have, the more important on-page factors are.
6 There are a million ifs, ors, buts . . . I am attempting a concise summary. Exceptions to EACH of the POSITIVE ON-Page factors are frequent and many. However, I feel that it is important to score highly on as many factors as possible, since factor weight and even factor consideration are changing constantly - CYA. Not to mention the other SEs.
7 A few words about the LANGUAGE used on the Google site - in a phrase - "soft spoken". We see it everywhere these days. I am referring to understatement, sometimes even to the point of confusion. "significant", "may", etc. For example, when Google states that maybe it might not be a good idea to do a particular thing, what they SOMETIMES really mean is "If you do it, you are history". Some Google suggestions are actually commands (STRONG HINTS) in disguise. At some point, you begin to realize this. Google just can't tell us everything, literally. Soooooooooo,
8 LISTEN UP! Read the rules. Read between the lines. Carefully.
Differentiate. Project. Guess real hard for your situation.

Webmaster Guidelines

How does Google rank pages?

Google Facts and Fiction

Search Engine Optimizers



"These optimization opinions are too strong - Too much speculation - I wanna see your SEO data! ". . . OK. Here it is -

Google Search Engine Optimization Forums



   1    NOT A Google, Inc. Site
2 In no way, did this data come directly from Google, Inc.
3 This page consists of a compilation of public information, commonly available on the internet, at multiple sites, as well as public webmaster forums, and simple manual tests.
4 The opinions stated above are merely the often misguided personal opinions of the author.
5 I am not privy to any inside information.
6 This information is continually changing, and may not be relevant when you read it.
7 Although the author makes every effort to verify the information on this page, no information on this page is guaranteed to be correct, and any data contained herein may be erroneous.


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