Performance
· 22 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.
1.58 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
4.21 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
139 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.009
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
2.22 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.
4.24 s
Page Load Progression
FPage Weight BudgetAction3.2 MB transferred, 68 requestsFIX
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.
Source: web.dev
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
DThird-Party ImpactAction99% third-party, 0 ms blockingFIX
DJS BundlesAction16 scripts, 361 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202607080101/pubads_impl.js | 192 KB | 145 KB (75%) | ✓ | 3rd |
| https://assets.tumblr.com/client/prod/standalone/tumblelog/index.build.js?_v=1ba6c357e857b5c4be7fca41bb39029a | 190 KB | 72 KB (41%) | ✓ | 3rd |
| https://assets.tumblr.com/client/prod/standalone/tumblelog/index.build.js?_v=1ba6c357e857b5c4be7fca41bb39029a | 190 KB | 72 KB (41%) | ✓ | 3rd |
| https://assets.tumblr.com/client/prod/standalone/tumblelog/index.build.js?_v=1ba6c357e857b5c4be7fca41bb39029a | 0 KB | 72 KB (41%) | ✓ | 3rd |
| https://securepubads.g.doubleclick.net/tag/js/gpt.js | 35 KB | — | ✓ | 3rd |
| https://assets.tumblr.com/assets/scripts/pre_tumblelog.js?_v=b9f848c06fcba7eaf305d4a7cb7a1b98 | 1 KB | — | ✓ | 3rd |
| https://www.google-analytics.com/analytics.js | 21 KB | — | ✓ | 3rd |
| https://helmi.fm/assets/scripts/tumblr/dashboard/showads.js | 0 KB | — | ✓ | 1st |
| https://assets.tumblr.com/default-theme/r1/main-min.js | 38 KB | — | ✓ | 3rd |
| https://assets.tumblr.com/assets/scripts/tumblr/utils/exceptions.js?_v=df137e9dabab81ff77ffb6ada9918aac | 3 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
DPage Weight InventoryAction68 resources · 3.2 MB · 361 KB savings availableFIX
~361.4 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 68 resources | 3.2 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization21 images, 0 KB saveableREVIEW
CJS Execution CostAction1189ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://assets.tumblr.com/client/prod/standalone/tumblelog/index.build.js?_v=1ba6c357e857b5c4be7fca41bb39029a | 445ms | 307ms | 76ms | 3rd |
| https://helmi.fm/ | 304ms | 10ms | 2ms | 1st |
| Unattributable | 162ms | 6ms | 0ms | 1st |
| https://assets.tumblr.com/default-theme/r1/main-min.js | 106ms | 87ms | 9ms | 3rd |
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202607080101/pubads_impl.js | 94ms | 60ms | 28ms | 3rd |
| https://assets.tumblr.com/assets/scripts/pre_tumblelog.js?_v=b9f848c06fcba7eaf305d4a7cb7a1b98 | 77ms | 3ms | 0ms | 3rd |
BHTTP/3 (QUIC)HTTP/3 not advertisedREVIEW
BMain HTML Cache-ControlNo Cache-Control header on main HTML responseREVIEW
BServer-Timing ObservabilityNo Server-Timing header foundREVIEW
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 Loading4 fonts (128 KB)PASS
Web fonts
4
128 KB total
Render-blocking
0
of 4
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
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 ~18 KB and ~36 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+Compression AlgorithmMain response uses brotliPASS
A+LCP Image PreloadLCP preload audit not availablePASS
A+Server Response Intelligence2 server-response signal(s) detectedPASS
Network Waterfall68 requests over 2383msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
assets.tumblr.com assets.tumblr.com | Other | 445ms | 190 KB | 41% | $6/mo | Costly |
assets.tumblr.com assets.tumblr.com | Other | 106ms | 38 KB | — | $1/mo | Optional |
securepubads.g.doubleclick.net securepubads.g.doubleclick.net | Other | 94ms | 192 KB | 75% | $1/mo | Optional |
assets.tumblr.com assets.tumblr.com | Other | 77ms | 1 KB | — | $1/mo | Optional |
These scripts may cost more than they're worth
- assets.tumblr.com adds 445ms and costs ~$6/month
61% of JavaScript execution time comes from third-party scripts.
Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.
Learn more ▾ ▴
Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.
Source: web.dev / HTTP Archive Web Almanac
assets.tumblr.com takes 445ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
75% of securepubads.g.doubleclick.net's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
Image Optimization13 images, 759 KB total, 536 KB wastedINFO
Image Optimization Audit
Total Images
13
Total Size
759 KB
Oversized
10
Wasted
536 KB