Skip to content
https://www.retool.com

Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
75
GRADE
C
FIX
4
REVIEW
3
PASS
7
INFO
2

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
29
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
77
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

4.06 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

16.18 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

3.63 s

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.000

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

8.54 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

23.33 s

Page Load Progression

925 ms
1.9 s
2.8 s
3.7 s
4.6 s
5.5 s
6.5 s
7.4 s
Checks
16
7 PASS 3 REVIEW 4 FIX
D
Page Weight Budget
Action
2.5 MB transferred, 182 requests
FIX
2.5 MB transferred, 182 requests
Warning::
Page weighs 8.4 MB (2.5 MB transferred)
Warning::
JavaScript is 1.8 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.8 MB
Warning::
182 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.53 g CO2 per page load
2.5 MB / 2.4 MB budget
2.5 MB transferred
182 requests
0.53 g CO2 per page load
JavaScript 1.8 MiB 71%
Images 433.3 KiB 17%
Fonts 162.3 KiB 6%
CSS 83.9 KiB 3%
HTML 54.0 KiB 2%
Other 8.2 KiB 0%
Other 2.9 KiB 0%
Other 2.5 KiB 0%
Other 1.3 KiB 0%
Other 596 B 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (2.5 MiB of 2.5 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Execution Cost
Action
18863ms total JS execution
FIX
18863ms total JS execution
Warning::
https://retool.com/_next/static/chunks/1e0b84fcd5f...: 3854ms CPU time
Warning::
https://retool.com/_next/static/chunks/255d11a380c...: 3836ms CPU time
Warning::
https://retool.com/: 3475ms CPU time
Warning::
Unattributable: 2648ms CPU time
Warning::
https://js.hs-analytics.net/analytics/177559380000...: 960ms CPU time
Warning::
Third-party scripts: 18863ms (100% of total)

Main Thread Breakdown

Script Evaluation 48% Other 29% Rendering 8% Style & Layout 8% Script Parsing & Compilation 4%
ScriptTotalScriptingParse/CompileParty
https://retool.com/_next/static/chunks/1e0b84fcd5f11d4b.js3854ms1190ms18ms3rd
https://retool.com/_next/static/chunks/255d11a380c0e2b5.js3836ms3074ms34ms3rd
https://retool.com/3475ms24ms41ms3rd
Unattributable2648ms225ms0ms3rd
https://js.hs-analytics.net/analytics/1775593800000/7660877.js960ms732ms10ms3rd
https://scripts.clarity.ms/0.8.59/clarity.js705ms644ms22ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-WHDC2N5543ms466ms45ms3rd
https://cdn.intellimize.co/snippet/117371543.js438ms367ms61ms3rd
https://www.googletagmanager.com/gtag/js?id=G-Y9141XKQB4&cx=c&gtm=4e6461h2407ms341ms54ms3rd
https://retool.com/_next/static/chunks/8c85ef5c5e11eff8.js388ms386ms1ms3rd

Showing top 10 of 21 scripts

F
JS Bundles
Action
74 scripts, 538 KB unused
FIX
74 scripts, 538 KB unused
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-WHD...: 108 KB unused (69%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://retool.com/_next/static/chunks/0659e107baf...: 87 KB unused (95%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-Y914...: 70 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-WHD...: 65 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.intellimize.co/snippet/117371543.js: 44 KB unused (36%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 538 KB
538 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtm.js?id=GTM-WHDC2N5&l=dataLayer157 KB108 KB (69%)✓3rd
https://retool.com/_next/static/chunks/0659e107baf05443.js91 KB87 KB (95%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-Y9141XKQB4&cx=c&gtm=4e6461h2176 KB70 KB (40%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-WHDC2N5157 KB65 KB (41%)✓3rd
https://cdn.intellimize.co/snippet/117371543.js125 KB44 KB (36%)✓3rd
https://retool.com/_next/static/chunks/9a0bb78c98ed5400.js43 KB43 KB (100%)✓3rd
https://script.hotjar.com/modules.6a0f3932cb1341a35c18.js57 KB38 KB (67%)✓3rd
https://retool.com/_next/static/chunks/1e0b84fcd5f11d4b.js62 KB33 KB (53%)✓3rd
https://connect.facebook.net/en_US/fbevents.js95 KB30 KB (31%)✓3rd
https://retool.com/_next/static/chunks/255d11a380c0e2b5.js72 KB22 KB (31%)✓3rd

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

B
Image Optimization
62 images, 0 KB saveable
REVIEW
62 images, 0 KB saveable
Info::
All images are well-optimized
62 images 433 KB
0 oversized -0 KB
58 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

B
HTTP Caching
public, max-age=0, must-revalidate
REVIEW
public, max-age=0, must-revalidate
Info::
Cache-Control header is set
Got: public, max-age=0, must-revalidate
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

public, max-age=0, must-revalidate

DirectiveValueMeaning
public—Any cache may store this response
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
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
3 fonts (162 KB)
PASS
3 fonts (162 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

162 KB total

Render-blocking

0

of 3

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s 14.0 s 16.0 s FCP 4.1 s LCP 16.2 shttps://retool.com/_next/static/media/PxGrotesk_Bold-s.p.b67bfcd7.woff2PxGrotesk_Bold-s.p.b67b... https://retool.com/_next/static/media/PxGrotesk_Bold-s.p.b67bfcd7.woff2 — 21.3 KiB — 0 ms — font-display: swaphttps://retool.com/_next/static/media/Px_Grotesk_Regular-s.p.9f07335c.woff2Px_Grotesk_Regular-s.p.... https://retool.com/_next/static/media/Px_Grotesk_Regular-s.p.9f07335c.woff2 — 50.4 KiB — 0 ms — font-display: swaphttps://retool.com/_next/static/media/SaansVF-s.p.84a2bbd5.woff2SaansVF-s.p.84a2bbd5.woff2 https://retool.com/_next/static/media/SaansVF-s.p.84a2bbd5.woff2 — 90.7 KiB — 0 ms — font-display: swap
PxGrotesk_Bold-s.p.b67b... woff2 swap
Size 21 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Px_Grotesk_Regular-s.p.... woff2 swap
Size 50 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
SaansVF-s.p.84a2bbd5.woff2 woff2 swap
Size 91 KB
Load time 0 ms
Start 0 ms
Risk FOUT — 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)
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
34 hints, 0 missing preconnects
PASS
34 hints, 0 missing preconnects
Info::
Page uses 34 resource hint(s)

Current Resource Hints

preconnect
6
preload
+18
28
dns-prefetch
—
prefetch
—

34 resource hints configured

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
Network Waterfall
182 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100% of JavaScript execution is third-party
First-party Third-party 18863ms · 1175KB · €302/mo
retool.com
Other
Costly
Execution 3854ms
Transfer 62 KB
Unused 53%
Monthly Cost €62/mo
retool.com
Other
Costly
Execution 3836ms
Transfer 72 KB
Unused 31%
Monthly Cost €61/mo
retool.com
Other
Costly
Execution 3475ms
Transfer 48 KB
Monthly Cost €56/mo
Unattributable
Other
Costly
Execution 2648ms
Transfer 0 KB
Monthly Cost €42/mo
HubSpot Analytics
Analytics
Costly
Execution 960ms
Transfer 42 KB
Monthly Cost €15/mo
Microsoft Clarity
Session Replay
Costly
Execution 705ms
Transfer 26 KB
Monthly Cost €11/mo
Google Tag Manager
Tag Manager
Costly
Execution 543ms
Transfer 157 KB
Unused 41%
Monthly Cost €9/mo
cdn.intellimize.co
Other
Costly
Execution 438ms
Transfer 125 KB
Unused 36%
Monthly Cost €7/mo
Google Tag Manager
Tag Manager
Costly
Execution 407ms
Transfer 176 KB
Unused 40%
Monthly Cost €6/mo
retool.com
Other
Costly
Execution 388ms
Transfer 1 KB
Monthly Cost €6/mo
Google Tag Manager
Tag Manager
Costly
Execution 298ms
Transfer 157 KB
Unused 69%
Monthly Cost €5/mo
Facebook Pixel
Advertising
Costly
Execution 215ms
Transfer 95 KB
Unused 31%
Monthly Cost €3/mo
Hotjar
Session Replay
Optional
Execution 197ms
Transfer 57 KB
Unused 67%
Monthly Cost €3/mo
Facebook Pixel
Advertising
Optional
Execution 196ms
Transfer 39 KB
Monthly Cost €3/mo
p.retool.com
Other
Optional
Execution 144ms
Transfer 22 KB
Monthly Cost €2/mo
p.retool.com
Other
Optional
Execution 135ms
Transfer 3 KB
Monthly Cost €2/mo
Twitter/X Pixel
Advertising
Optional
Execution 118ms
Transfer 13 KB
Monthly Cost €2/mo
retool.com
Other
Optional
Execution 106ms
Transfer 17 KB
Monthly Cost €2/mo
Google Analytics
Analytics
Optional
Execution 89ms
Transfer 21 KB
Monthly Cost €1/mo
retool.com
Other
Optional
Execution 57ms
Transfer 23 KB
Monthly Cost €1/mo
LinkedIn Insight
Advertising
Optional
Execution 54ms
Transfer 19 KB
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • retool.com adds 3854ms and costs ~€62/month
  • retool.com adds 3836ms and costs ~€61/month
  • retool.com adds 3475ms and costs ~€56/month
  • Unattributable adds 2648ms and costs ~€42/month
  • HubSpot Analytics adds 960ms and costs ~€15/month
  • Microsoft Clarity adds 705ms and costs ~€11/month
  • Google Tag Manager adds 543ms and costs ~€9/month
  • cdn.intellimize.co adds 438ms and costs ~€7/month
  • Google Tag Manager adds 407ms and costs ~€6/month
  • retool.com adds 388ms and costs ~€6/month
  • Google Tag Manager adds 298ms and costs ~€5/month
  • Facebook Pixel adds 215ms 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

retool.com takes 3854ms 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

53% of retool.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

retool.com takes 3836ms 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

retool.com takes 3475ms 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 2648ms 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

HubSpot Analytics takes 960ms 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

Microsoft Clarity takes 705ms 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 543ms 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

cdn.intellimize.co takes 438ms 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 407ms 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

retool.com takes 388ms 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 298ms 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

69% of Google Tag Manager'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

Facebook Pixel takes 215ms 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

67% of Hotjar'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

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

Send Feedback