Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
C
Image Optimization
Action
42 images, 0 KB saveable
REVIEW
42 images, 0 KB saveable
Warning::
!
https://s3.images-iherb.com/cms/logos/rewards/iHer... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
!
https://cloudinary.images-iherb.com/image/upload/f... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
42images304 KB
0oversized-0 KB
22legacy format
19missing dimensionsCLS risk
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Why this matters
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
✓
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
8 fonts (598 KB)
PASS
8 fonts (598 KB)
Info::
i
8 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
8
598 KB total
Render-blocking
0
of 8
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
lato-regular-v2.woff2woff2swap
Size33 KB
Load time140 ms
Start477 ms
RiskFOUT — text flashes from fallback to web font
lato-bold-v2.woff2woff2swap
Size32 KB
Load time140 ms
Start478 ms
RiskFOUT — text flashes from fallback to web font
droidkufi-regular-v2.woff2woff2swap
Size31 KB
Load time143 ms
Start478 ms
RiskFOUT — text flashes from fallback to web font
notosans-regular.woff2woff2swap
Size117 KB
Load time156 ms
Start478 ms
RiskFOUT — text flashes from fallback to web font
Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
notosans-light.woff2woff2swap
Size118 KB
Load time160 ms
Start478 ms
RiskFOUT — text flashes from fallback to web font
Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
notosans-medium.woff2woff2swap
Size119 KB
Load time163 ms
Start478 ms
RiskFOUT — text flashes from fallback to web font
Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
notosans-bold.woff2woff2swap
Size115 KB
Load time165 ms
Start478 ms
RiskFOUT — text flashes from fallback to web font
Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
KFO7CnqEu92Fr1ME7kSn66a...woff2swap
Size34 KB
Load time75 ms
Start2.8 s
RiskFOUT — text flashes from fallback to web font
Optimization checklist
Preload critical fonts (priority=high)
Use woff2 format for all fonts
Set font-display to swap, optional, or fallback
Subset large fonts (≤100 KB each)
Fixing the unchecked items could save ~234 KB and ~468 ms
A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
✓
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
✓
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
✓
No resource hint issues
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
✓
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall
139 requests over 33187ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100%of JavaScript execution is third-party
First-party Third-party21453ms · 1513KB · $285/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
es.iherb.com
es.iherb.com
Other
11585ms
85 KB
—
$154/mo
Costly
s3.images-iherb.com
s3.images-iherb.com
Other
2893ms
452 KB
62%
$38/mo
Costly
s3.images-iherb.com
s3.images-iherb.com
Other
2010ms
35 KB
—
$27/mo
Costly
s3.images-iherb.com
s3.images-iherb.com
Other
1480ms
462 KB
44%
$20/mo
Costly
es.iherb.com
es.iherb.com
Other
1195ms
103 KB
32%
$16/mo
Costly
Unattributable
Unattributable
Other
1162ms
0 KB
—
$15/mo
Costly
www.gstatic.com
www.gstatic.com
Other
297ms
0 KB
49%
$4/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
271ms
140 KB
42%
$4/mo
Costly
js-agent.newrelic.com
js-agent.newrelic.com
Other
217ms
34 KB
—
$3/mo
Costly
es.iherb.com
es.iherb.com
Other
186ms
0 KB
—
$2/mo
Optional
gtm-metrics.iherb.com
gtm-metrics.iherb.com
Other
107ms
188 KB
36%
$1/mo
Optional
consent.truste.com
consent.truste.com
Other
51ms
13 KB
—
$1/mo
Optional
es.iherb.com
Other
Costly
Execution11585ms
Transfer85 KB
Monthly Cost$154/mo
s3.images-iherb.com
Other
Costly
Execution2893ms
Transfer452 KB
Unused62%
Monthly Cost$38/mo
s3.images-iherb.com
Other
Costly
Execution2010ms
Transfer35 KB
Monthly Cost$27/mo
s3.images-iherb.com
Other
Costly
Execution1480ms
Transfer462 KB
Unused44%
Monthly Cost$20/mo
es.iherb.com
Other
Costly
Execution1195ms
Transfer103 KB
Unused32%
Monthly Cost$16/mo
Unattributable
Other
Costly
Execution1162ms
Transfer0 KB
Monthly Cost$15/mo
www.gstatic.com
Other
Costly
Execution297ms
Transfer0 KB
Unused49%
Monthly Cost$4/mo
Google Tag Manager
Tag Manager
Costly
Execution271ms
Transfer140 KB
Unused42%
Monthly Cost$4/mo
js-agent.newrelic.com
Other
Costly
Execution217ms
Transfer34 KB
Monthly Cost$3/mo
es.iherb.com
Other
Optional
Execution186ms
Transfer0 KB
Monthly Cost$2/mo
gtm-metrics.iherb.com
Other
Optional
Execution107ms
Transfer188 KB
Unused36%
Monthly Cost$1/mo
consent.truste.com
Other
Optional
Execution51ms
Transfer13 KB
Monthly Cost$1/mo
These scripts may cost more than they're worth
es.iherb.com adds 11585ms and costs ~$154/month
s3.images-iherb.com adds 2893ms and costs ~$38/month
s3.images-iherb.com adds 2010ms and costs ~$27/month
s3.images-iherb.com adds 1480ms and costs ~$20/month
es.iherb.com adds 1195ms and costs ~$16/month
Unattributable adds 1162ms and costs ~$15/month
www.gstatic.com adds 297ms and costs ~$4/month
Google Tag Manager adds 271ms and costs ~$4/month
js-agent.newrelic.com adds 217ms and costs ~$3/month
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
Why this matters
When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.
Learn more ▾▴
Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.
Source: web.dev
es.iherb.com takes 11585ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
s3.images-iherb.com takes 2893ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
62% of s3.images-iherb.com's code is unused. The script may be loading features you don't use.
Why this matters
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
s3.images-iherb.com takes 2010ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
s3.images-iherb.com takes 1480ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
es.iherb.com takes 1195ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
Unattributable takes 1162ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.gstatic.com takes 297ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
Google Tag Manager takes 271ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
js-agent.newrelic.com takes 217ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
Why this matters
This script has high main-thread execution time — optimize hot paths or defer.