Performance
· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
2.08 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
3.19 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
27 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.120
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
2.58 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.
3.39 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DJS BundlesAction16 scripts, 445 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-CSLL4ZEK4L&cx=c>m=4e64f0 | 147 KB | 106 KB (72%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-ZY6FM95CS5&cx=c>m=4e64f0 | 153 KB | 63 KB (41%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-CSLL4ZEK4L | 147 KB | 62 KB (42%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-KV978ZL | 139 KB | 57 KB (41%) | ✓ | 3rd |
| https://www.irs.gov/pub/js/js_uQ3AXRedwNs815Y7AO31iI36vlbr_6NIRZCoLu8BbEY.js?scope=footer&delta=2&language=en&theme=pup_irs&include=eJx1kWGSwyAIhS9k4pEcVGrYGnEQu-3tN2k3abLT_SO876GCQggskbi4GUtvFs7afVNMqAZiVIbysFsyXoSLGs-sTQWq3TNXBR0VOpqVK99QDkSZs1I1YeKGxb7C6PGykSi9Qh5fykRQyPBAsR4nuBFLM3jXTOW6Vf5Kk5hTRqeQbFqWv3qEL7if4Wxqr26ZHFsjT5l0nXOm4tYuPcjT99DQpswe8tBIcbggaBdsTzdcMZKyuJp7onJ4yM_2J_isJGn7LUGo6hvPoGEaJqQ06RtigmH9qwMp_dzcSpc4TDxjhYRDAOHeMO9uQ5Dl7H3XSzuo5KArB55rRkX7D_8Bj-nlkA | 67 KB | 48 KB (71%) | ✓ | 3rd |
| https://resources.digital-cloud-gov.medallia.com/wdcgov/20103/onsite/generic1776352584096.js | 82 KB | 47 KB (57%) | ✓ | 3rd |
| https://www.irs.gov/pub/js/js_w8fM3HiCn-P-n7TMi9seyjEJrCmAhX-z8-63A6hCyVU.js?scope=footer&delta=0&language=en&theme=pup_irs&include=eJx1kWGSwyAIhS9k4pEcVGrYGnEQu-3tN2k3abLT_SO876GCQggskbi4GUtvFs7afVNMqAZiVIbysFsyXoSLGs-sTQWq3TNXBR0VOpqVK99QDkSZs1I1YeKGxb7C6PGykSi9Qh5fykRQyPBAsR4nuBFLM3jXTOW6Vf5Kk5hTRqeQbFqWv3qEL7if4Wxqr26ZHFsjT5l0nXOm4tYuPcjT99DQpswe8tBIcbggaBdsTzdcMZKyuJp7onJ4yM_2J_isJGn7LUGo6hvPoGEaJqQ06RtigmH9qwMp_dzcSpc4TDxjhYRDAOHeMO9uQ5Dl7H3XSzuo5KArB55rRkX7D_8Bj-nlkA | 52 KB | 22 KB (42%) | ✓ | 3rd |
| https://static.addtoany.com/menu/modules/core.ydpp7jcu.js | 26 KB | 21 KB (82%) | ✓ | 3rd |
| https://www.irs.gov/static_assets/js/libs/jquery.min.js | 30 KB | 20 KB (69%) | ✓ | 3rd |
| https://www.irs.gov/pub/js/js_KDJrWUHMfAKem9afv9zeDu0oqcEh3pcAadDZ4AT7VL4.js?scope=header&delta=0&language=en&theme=pup_irs&include=eJx1kWGSwyAIhS9k4pEcVGrYGnEQu-3tN2k3abLT_SO876GCQggskbi4GUtvFs7afVNMqAZiVIbysFsyXoSLGs-sTQWq3TNXBR0VOpqVK99QDkSZs1I1YeKGxb7C6PGykSi9Qh5fykRQyPBAsR4nuBFLM3jXTOW6Vf5Kk5hTRqeQbFqWv3qEL7if4Wxqr26ZHFsjT5l0nXOm4tYuPcjT99DQpswe8tBIcbggaBdsTzdcMZKyuJp7onJ4yM_2J_isJGn7LUGo6hvPoGEaJqQ06RtigmH9qwMp_dzcSpc4TDxjhYRDAOHeMO9uQ5Dl7H3XSzuo5KArB55rRkX7D_8Bj-nlkA | 1 KB | — | ✓ | 3rd |
Consider code splitting or tree shaking to reduce unused code.
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.
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.
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.
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.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
FPage Weight InventoryAction52 resources · 1.6 MB · 445 KB savings availableFIX
~445.0 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 52 resources | 1.6 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CPage Weight BudgetAction1.6 MB transferred, 52 requestsREVIEW
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.
Source: web.dev
Subset fonts to include only used characters, or switch to system font stacks.
Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).
Source: web.dev font loading
CImage OptimizationAction23 images, 0 KB saveableREVIEW
Set explicit width and height to prevent CLS.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
BJS Execution Cost569ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.irs.gov/pub/js/js_w8fM3HiCn-P-n7TMi9seyjEJrCmAhX-z8-63A6hCyVU.js?scope=footer&delta=0&language=en&theme=pup_irs&include=eJx1kWGSwyAIhS9k4pEcVGrYGnEQu-3tN2k3abLT_SO876GCQggskbi4GUtvFs7afVNMqAZiVIbysFsyXoSLGs-sTQWq3TNXBR0VOpqVK99QDkSZs1I1YeKGxb7C6PGykSi9Qh5fykRQyPBAsR4nuBFLM3jXTOW6Vf5Kk5hTRqeQbFqWv3qEL7if4Wxqr26ZHFsjT5l0nXOm4tYuPcjT99DQpswe8tBIcbggaBdsTzdcMZKyuJp7onJ4yM_2J_isJGn7LUGo6hvPoGEaJqQ06RtigmH9qwMp_dzcSpc4TDxjhYRDAOHeMO9uQ5Dl7H3XSzuo5KArB55rRkX7D_8Bj-nlkA | 184ms | 81ms | 4ms | 3rd |
| Unattributable | 97ms | 3ms | 0ms | 3rd |
| https://www.irs.gov/ | 81ms | 2ms | 1ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-ZY6FM95CS5&cx=c>m=4e64f0 | 77ms | 62ms | 15ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-KV978ZL | 73ms | 56ms | 14ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-CSLL4ZEK4L | 59ms | 49ms | 9ms | 3rd |
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+Font Loading3 fonts (290 KB)PASS
Web fonts
3
290 KB total
Render-blocking
0
of 3
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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 ~107 KB and ~214 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
Network Waterfall52 requests over 2474msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.irs.gov www.irs.gov | Other | 184ms | 52 KB | 42% | $2/mo | Optional |
Unattributable Unattributable | Other | 97ms | 0 KB | — | $1/mo | Optional |
www.irs.gov www.irs.gov | Other | 81ms | 18 KB | — | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 77ms | 153 KB | 41% | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 73ms | 139 KB | 41% | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 59ms | 147 KB | 42% | $1/mo | Optional |
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
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