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radiko.jp

https://radiko.jp· First analyzed 22 Apr 2026· Updated 22 Apr 2026
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radiko.jp
Desktop screenshot of radiko.jp
Mobile screenshot of radiko.jp
Mobile

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Hosting Provider

NTT SmartConnect Corporation

IP Address

203.211.199.120

Site Location

🇯🇵 Japanvia tld

Server Location

🇯🇵 Chiyoda City, Japan

ASN

AS7671

Organization

NTT SmartConnect Corporation

Server

Nginx

CDN

Cloudflare

WAF

Cloudflare

Nameservers

quincy.ns.cloudflare.com.lovisa.ns.cloudflare.com.

Performance

73

Core Web Vitals

Weight

First Contentful Paint
7.8 s10%
Speed Index
10.2 s10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
3.8 MB
134 requests
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Hosting
NTT SmartConnect Corporation
CDN
Cloudflare

Technology Stack

10 Technologies Detected

Libraries

3
jQueryv1.9.0
jQuery UI
Moment.js

Analytics

2
Google Analytics
Facebook Pixel

UI Components

1
Slick Carousel

CSS Frameworks

1
Tailwind CSS

Tag Managers

1
Google Tag Manager

Advertising

1
Google Ads

Web Servers

1
Nginx

SEO Analysis

D59/100
17
7
1
Meta Tags8/15
Content10/12
Headings3/8
Technical14/25
E-E-A-T0/7
Images2/7
Links5/5
URL5/5
Social5/5
Freshness0/4
Mobile4/4
Indexability3/3
R
radiko.jpradiko.jp

radiko

radiko(ラジコ)はスマートフォンやアプリ・パソコンでラジオが聴ける無料のサービスです。1週間以内に放送された番組が聴けるタイムフリー聴取機能や、全国のラジオが聴き放題のラジコプレミアムも！AM・FMラジオ対応

Title Length6 chars

Recommended: 50-60 chars (~35px / 580px)

Description Length107 chars

Recommended: 120-160 chars

Issues (1)

  • • Missing H1 tag — every page should have exactly one H1

8 issues found

Upgrade to view details

Crawlability

Sitemap

Type: index

1 URLs

1 sub-sitemaps

robots.txt

21 rules

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

F32/100
Bot Access
20/25
Machine Read.
2/25
Schema Data
0/25
Citation
10/25

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
blockquotesheader/footer
Text ratio:3%
Words:296
Token eff.:Too Short
Sections/1K:23.6
Depth:2/5

Structured Data

No Schema

Citation Readiness

Opening Summary15w
Descriptive Headingsavg 1w
Canonical URL
Open Graph3/3
Twitter Card3/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (10)
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.
D
50/100
6
Passed
6
Critical
3
Warnings
Images & Alt Text
15/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
11/20
Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.
Forms & Inputs
2/15
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
6/15
Ensures all interactive elements are reachable and operable via keyboard (tab, enter, escape).
ARIA & Roles
1/15
Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.
5 recommendations
  • •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.
6/100
F
476 mg
CO₂e / view
3.8 MB
Page Weight
15%
Cleaner Than
New Visitor
544 mg
vs
Returning (cached)
272 mg
Annual (10K/mo)
57.1 kg
Emission Segments
Data Center
106 mg
Network
114 mg
Device
255 mg
Resource Breakdown
JavaScript
2.7 MB
Images
53.8 KB
CSS
299.4 KB
HTML
16.3 KB
Other
732.4 KB
Green Hosting Not Verified
NTT SmartConnect Corporation
7 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
F

Security Score

31%Critical
Interactive

HTTPS

No WAF

60d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Sectigo Limited

Key Algorithm

RSA (2048 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.2

HTTP Protocol

HTTP/1.1

Valid From

21.05.2025

Valid Until

21.06.2026

OCSP Stapling

Enabled

Subject Alternative Names (2)

radiko.jpwww.radiko.jp

SHA-256 Fingerprint

30:24:4E:12:21:BA:82:C4:CD:E6:D4:D6:30:BA:A4:E4:91:C2:F6:09...

Top Recommendations

Security recommendation preview

Upgrade to view recommendations
Upgrade to view header details

HTTP Headers

Developer Console

accept-ranges
bytes
connection
keep-alive
content-length
16400
content-type
text/html
date
Wed, 22 Apr 2026 17:41:42 GMT
etag
"69c20ce7-4010"
Good Warning Issue

Email Infrastructure

Google Workspace

Score

90

SPF
DKIM
DMARC

DMARC Policy

None (Monitor Only)

MX Records (5)

alt1.aspmx.l.google.com
alt4.aspmx.l.google.com
alt3.aspmx.l.google.com
alt2.aspmx.l.google.com

+1 more

Domain Information

radiko.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,initial-scale=1.0
3 recommendations
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

-apple-system

WCAG Partial
55/100
Readability
/30
13/30

13px · LH 1.70

Hierarchy
/20
8/20
WCAG
/25
14/25

1.47:1 min contrast

Performance
/25
20/25

System fonts

Heading Font

-apple-system

Sans

Body Font

-apple-system

Sans13px

Contrast Ratio

1.47:1

15 issues

Reading Comfort

~69 CPL

Optimal (45–75)
20px
h2
13px
p

❌ Critical: 13px body text is too small. Minimum 14px, recommend 16px+.

✅ Optimal line length: ~68 chars/line (ideal 45–75 CPL).

⚠️ Partial contrast: 15 elements below WCAG AA threshold (min 1.5:1).

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

✅ System fonts: Zero font loading delay — best possible LCP impact.

Color Palette

6 unique colors
4.35:1 AA Large Dark
#717b7d
Other· 54.1%
#ffffff
Background· 19.6%
#025475
Primary· 13.8%
#142e39
Secondary· 8.6%
#5c7074
Secondary· 2.4%

Business & Marketing Stack

5 Tools Detected

Enterprise

Behavior Analytics

2
Google Tag ManagerFree
Google AnalyticsFree

User behavior and product analytics

Advertising

1
Facebook PixelMid-Market

Ad platforms and retargeting pixels

Social Media

2
Facebook SDKFree
Twitter/X WidgetsFree

Social widgets and sharing tools

3

Categories

5

Total Tools

0

Enterprise

1

Mid-Market

Assessment: Sophisticated marketing and sales technology infrastructure

Sponsored

Scripts & Styles

30 Resources

20
Scripts
10
Styles
5
Async
0
Defer

Top Script Sources

local(13)connect.facebook.net(2)google-analytics.com(2)platform.twitter.com(1)cdn.treasuredata.com(1)

Website Identity

radiko.jp

Location detected: 🇯🇵 Japanvia tld
📧 Google Workspaceja

Sponsored

Last analyzed: 22 Apr 2026 at 17:42

Historical Analysis & Change Tracking