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gakken.co.jp

https://gakken.co.jp· First analyzed 28 Apr 2026· Updated 28 Apr 2026
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gakken.co.jp
Desktop screenshot of gakken.co.jp
Mobile screenshot of gakken.co.jp
Mobile

Sponsored

Hosting Provider

BroadBand Tower, Inc.

IP Address

203.216.223.33

Site Location

🇯🇵 Japanvia tld

Server Location

🇯🇵 Minato, Japan

ASN

AS9607

Organization

BroadBand Tower, Inc.

Server

Apache

CDN

CloudFront

Nameservers

ns00.vips.ne.jp.ns01.vips.ne.jp.

Performance

81

Core Web Vitals

Weight

First Contentful Paint
2.1 s10%
Speed Index
2.8 s10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
14.9 MB
78 requests

Image Optimization

Lazy Load
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Platform
AWS CloudFront
CDN
CloudFront

Technology Stack

5 Technologies Detected

Analytics

2
Google Analytics
Google Analytics 4

CSS Frameworks

1
Tailwind CSS

Fonts

1
Adobe Fonts (Typekit)

Web Servers

1
Apache

SEO Analysis

C67/100
18
9
0
Meta Tags7/15
Content11/12
Headings7/8
Technical16/25
E-E-A-T3/7
Images3/7
Links5/5
URL5/5
Social3/5
Freshness0/4
Mobile4/4
Indexability3/3
G
gakken.co.jpgakken.co.jp

ホーム | 株式会社学研ホールディングス

株式会社学研ホールディングスの公式サイト。企業概要、IR、社会・環境、採用などの企業情報のほか、学研グループの書籍、商品、サービス、教育などの各種事業のご紹介

Title Length20 chars

Recommended: 50-60 chars (~121px / 580px)

Description Length79 chars

Recommended: 120-160 chars

Issues (0)

    9 issues found

    Upgrade to view details

    Crawlability

    Sitemap

    Type: standard

    4,603 URLs

    robots.txt

    2 rules

    Sitemap reference found

    Allows all crawlers

    Local SEO

    Local Search Readiness

    6/100
    Poor
    2 13 2

    This site doesn't appear to be a local business. Local SEO signals are optional for non-local websites.

    Sponsored

    AI & LLM Readiness

    F36/100
    Bot Access
    20/25
    Machine Read.
    8/25
    Schema Data
    0/25
    Citation
    8/25

    AI Bot Access

    14/14 accessible
    AI Search
    OAI-SearchBot
    PerplexityBot
    Claude-SearchBot
    Gemini-Deep-Research
    DuckAssistBot
    Training
    GPTBot
    ClaudeBot
    Google-Extended
    Meta-ExternalAgent
    Bytespiderinfo
    Amazonbot
    Applebot-Extended
    CCBotinfo
    Fetch
    ChatGPT-User

    Machine Readability

    llms.txt
    llms-full.txt
    Semantic HTML
    Heading Hierarchy
    Text ratio:4%
    Words:1,028
    Token eff.:Optimal
    Sections/1K:18.5

    Structured Data

    No Schema

    Citation Readiness

    Opening Summary
    Descriptive Headingsavg 1.4w
    Canonical URL
    Open Graph3/3
    Twitter Card0/3
    Language Tag
    Publish Date
    Author Info
    Lists
    Tables
    TL;DR / Summary
    About Page Link
    Recommendations (12)
    AI readiness recommendation preview...
    Upgrade to view recommendations

    Sponsored

    Accessibility

    WCAG 2.1 Compliance

    Evaluates how accessible your website is for users with disabilities, based on WCAG 2.1 guidelines. Checks images, forms, keyboard navigation, ARIA roles, and color contrast.
    B
    78/100
    12
    Passed
    3
    Critical
    1
    Warnings
    Images & Alt Text
    20/20
    Checks if images have descriptive alt text for screen readers and visually impaired users.
    Semantic Structure
    13/20
    Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.
    Forms & Inputs
    15/15
    Verifies form fields have labels, error messages are clear, and inputs are properly associated.
    Color & Contrast
    15/15
    Tests text-to-background color contrast ratios against WCAG AA/AAA minimum requirements.
    Keyboard & Focus
    9/15
    Ensures all interactive elements are reachable and operable via keyboard (tab, enter, escape).
    ARIA & Roles
    6/15
    Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.
    1 recommendation
    • •Accessibility recommendation preview...
    Upgrade to view recommendations

    Carbon Footprint

    SWDM v4 · Eco-Score

    Carbon emissions estimated using the Sustainable Web Design Model v4 (SWDM v4). Factors in data center, network, and device energy across new and returning visitors. Grade thresholds based on HTTP Archive percentiles.
    13/100
    F
    1.89 g
    CO₂e / view
    14.9 MB
    Page Weight
    5%
    Cleaner Than
    New Visitor
    2.16 g
    vs
    Returning (cached)
    1.08 g
    Annual (10K/mo)
    226.4 kg
    Emission Segments
    Data Center
    421 mg
    Network
    453 mg
    Device
    1.01 g
    Resource Breakdown
    JavaScript
    211.8 KB
    Images
    14.1 MB
    CSS
    537.7 KB
    HTML
    11.4 KB
    Other
    52.9 KB
    Green Hosting Not Verified
    BroadBand Tower, Inc.
    7 recommendations
    • •Carbon footprint recommendation preview...
    Upgrade to view recommendations
    F

    Security Score

    21%Critical
    Interactive

    HTTPS

    No WAF

    88d

    Certificate Details

    Type

    Organization Validated (OV)

    Certificate Authority

    GlobalSign nv-sa

    Key Algorithm

    RSA (2048 bit)

    Signature

    SHA-256 with RSA

    TLS Version

    TLSv1.3

    HTTP Protocol

    HTTP/2

    Valid From

    24.06.2025

    Valid Until

    26.07.2026

    OCSP Stapling

    Enabled

    Subject Alternative Names (20)

    www.gakken.co.jpgakken-ps.co.jpgakken-educational.co.jpwww.glg.co.jpgakken-kyoikumirai.co.jpgakken-mesh.co.jpgakken-shuppanservice.co.jpgakken-shd.co.jp+12 more

    SHA-256 Fingerprint

    FD:62:41:C5:2A:87:9E:06:83:0F:AE:B0:50:86:E7:C7:81:D5:D9:79...

    Top Recommendations

    Security recommendation preview

    Upgrade to view recommendations
    Upgrade to view header details

    HTTP Headers

    Developer Console

    content-encoding
    📦 Gzip(gzip)
    content-type
    text/html; charset=UTF-8
    date
    Tue, 28 Apr 2026 06:39:25 GMT
    etag
    W/"dd31-6507b98d5fc40"
    last-modified
    Tue, 28 Apr 2026 02:00:35 GMT
    server
    Apache
    Good Warning Issue

    Email Infrastructure

    Microsoft 365

    Score

    65

    SPF
    DKIM
    DMARC

    DMARC Policy

    None (Monitor Only)

    MX Records (1)

    gakken-co-jp.mail.protection.outlook.com

    Domain Information

    gakken.co.jp

    DNSSEC
    Not Enabled

    Privacy & Compliance

    Cookie Consent Banner
    Privacy Policy
    Terms of Service

    GDPR Indicators

    Cookie consent banner detected
    Privacy policy page linked

    Mobile Compatibility

    Viewport & Responsive Test

    Tests how well your website works on mobile devices. Checks viewport configuration, responsive layout, touch targets, font readability, and simulates rendering across different screen sizes.
    D
    50/100
    Mobile Friendly1 breakpoint
    Viewport Meta
    The viewport meta tag tells mobile browsers how to scale the page. Without it, mobile devices render at desktop width.
    Responsive Design
    Uses CSS media queries or flexible layouts to adapt content to different screen sizes automatically.
    Touch Icons
    Apple touch icons and favicons displayed when users add the site to their home screen on mobile devices.
    Readable Font Size
    Base font size should be at least 16px on mobile to ensure text is readable without zooming.
    Relative Units
    Using em, rem, %, or vw instead of fixed px values allows content to scale properly across screen sizes.
    No H-Scroll Risk
    No elements wider than the viewport that would cause horizontal scrolling on mobile devices.
    Tap Targets OK
    Interactive elements (buttons, links) are at least 48x48px with enough spacing to prevent accidental taps.
    No Fixed Widths
    No elements with fixed pixel widths that could overflow on smaller screens and break the layout.
    Viewport
    width=device-width
    3 recommendations
    • •Mobile compatibility recommendation preview...
    Upgrade to view recommendations

    Typography & Readability

    游ゴシック Medium

    WCAG Partial
    63/100
    Readability
    /30
    24/30

    18px · LH 1.60

    Hierarchy
    /20
    7/20

    1x ratio

    WCAG
    /25
    17/25

    3.72:1 min contrast

    Performance
    /25
    15/25

    2 fonts · 2 req

    Heading Font

    游ゴシック Medium

    Sans18px

    Body Font

    游ゴシック Medium

    Sans18px

    Contrast Ratio

    3.72:1

    9 issues

    Reading Comfort

    ~59 CPL

    Optimal (45–75)
    18px
    h1
    48px
    h2
    16px
    h4
    18px
    p
    Perfect Fifth
    Scale

    ✅ Excellent readability: 18px body text is ideal for all devices.

    ✅ Optimal line spacing: 1.60 ratio (ideal range 1.4–1.6).

    ✅ Optimal line length: ~59 chars/line (ideal 45–75 CPL).

    ⚠️ Partial contrast: 9 elements below WCAG AA threshold (min 3.7:1).

    ❌ Missing H1: Every page should have exactly one H1 element for SEO and accessibility.

    ⚠️ Weak hierarchy: Headlines should be ≥2x body size for clear visual structure.

    AAdobe FontsBuy on MyFonts

    Color Palette

    8 unique colors
    Light
    #e8e9ea
    Other· 22%
    #64c6f3
    Primary· 41.300000000000004%
    #418c6a
    Secondary· 7.7%
    #dbdfcc
    Secondary· 6.5%
    #76b9bb
    Secondary· 4%
    #8dcdca
    Secondary· 2.9%
    #7bcff7
    Accent· 1%

    Business & Marketing Stack

    1 Tools Detected

    Growing

    Behavior Analytics

    1
    Google AnalyticsFree

    User behavior and product analytics

    1

    Categories

    1

    Total Tools

    0

    Enterprise

    0

    Mid-Market

    Assessment: Growing marketing technology adoption

    Sponsored

    Scripts & Styles

    25 Resources

    20
    Scripts
    5
    Styles
    2
    Async
    0
    Defer

    Top Script Sources

    local(17)use.typekit.net(1)googletagmanager.com(1)static.syncsearch.jp(1)

    Website Identity

    gakken.co.jp

    Location detected: 🇯🇵 Japanvia tld
    📧 Microsoft 365ja

    Social Profiles

    FacebookX (Twitter)

    Sponsored

    Last analyzed: 28 Apr 2026 at 06:40

    Historical Analysis & Change Tracking