Skip to main contentHow fast does the banner appear?
4.11 s
Median of 15 visits.
All 6 integrations, best first
- React3.57 s
- Script tag3.74 s
- Astro3.74 s
- Nuxt3.97 s
- TanStack Start4.11 s
- Next.js4.41 s
DidomiDidomiDidomi cookie banner: speed and features
In our tests with its TanStack Start integration, Didomi showed its cookie banner in a median 4.11 s on an emulated mid-tier phone. It delayed the main content by 1.28 s (95% interval 1.27 s to 1.37 s). Accept responded in 16 ms and Reject in 16 ms. It held trackers back in all 4 consent checks.
On desktop, the banner took 447 ms. Per vendor docs, Didomi supports IAB TCF, IAB GPP, Google Consent Mode v2, Google CMP certification and Global Privacy Control.
How fast is Didomi’s cookie banner?
On TanStack Start. We measured other CMPs on Next.js only, so this comparison uses Didomi’s other integrations.
Does it slow the page down?
+1.28 s95% interval 1.27 s to 1.37 s
Compared with the same page without a consent manager.
All 6 integrations, best first
- React1.10 s
- Next.js1.28 s
- Script tag1.28 s
- Nuxt1.28 s
- Astro1.28 s
- TanStack Start1.28 s
How fast does a click respond?
16 msOne visit measured
Reject responded in 16 ms. Under 200 ms feels instant.
All 6 integrations, best first
- Next.js16 ms
- Nuxt16 ms
- Astro16 ms
- TanStack Start16 ms
- React16 ms
- Script tag16 ms
Does it block trackers until consent?
4 of 4consent checks passed
No tracker ran and the page set no cookie before the visitor chose.
All 6 integrations, best first
- Next.js100%
- Nuxt100%
- Astro100%
- TanStack Start100%
- React100%
- Script tag100%
Which standards and features does Didomi support?
Each status comes from Didomi’s documentation. CookieBench does not test these features unless a line says so.
- Verified by test
- Per vendor docs
- Partial
- Not supported
- Unknown
| Feature | Status |
|---|---|
| IAB TCF | TCF v2.2 (vendor documentation, opens in a new tab) |
| IAB GPP | Per vendor docs (vendor documentation, opens in a new tab) |
| Google Consent Mode v2 | Per vendor docs (vendor documentation, opens in a new tab) |
| Google-certified CMP | Per vendor docs (vendor documentation, opens in a new tab) |
| Global Privacy Control | Per vendor docs (vendor documentation, opens in a new tab) |
| Feature | Status |
|---|---|
| Geo-targeted banners | Per vendor docs (vendor documentation, opens in a new tab) |
| Script blocking | Tag-based (vendor documentation, opens in a new tab) |
| Consent records | Per vendor docs (vendor documentation, opens in a new tab) |
| Cookie scanning | Per vendor docs (vendor documentation, opens in a new tab) |
| Feature | Status |
|---|---|
| Open source | Proprietary (vendor documentation, opens in a new tab) |
| Self-hostable | Assets through your domain (vendor documentation, opens in a new tab) |
| Headless UI | Per vendor docs (vendor documentation, opens in a new tab) |
| TypeScript types | React SDK only (vendor documentation, opens in a new tab) |
| Feature | Status |
|---|---|
| Free tier | Contact sales (vendor documentation, opens in a new tab) |
Which frameworks does Didomi support?
- First-party SDKs
- React
- Script tag
- Supported
- Measured in this run
- Script tag, React, Next.js, Nuxt, Astro and TanStack Start
Support per Didomi’s documentation.
Didomi’s results by framework, mobile (emulated)
Each row is a separate app. We measured each one against the same app without a consent manager. The rows compare integrations, not frameworks.
| Framework | Banner appears | Page slowed by | Click responds in | Trackers blocked |
|---|---|---|---|---|
| Script tag | 3.74 s | +1.28 s95% interval 1.27 s to 1.29 s | 16 msOne visit measured | 4 of 4 passed |
| React | 3.57 s | +1.10 s95% interval 1.07 s to 1.13 s | Under 16 msOne visit measured | 4 of 4 passed |
| Next.jsShared with every CMP | 4.41 s | +1.28 s95% interval 1.26 s to 1.29 s | 16 msOne visit measured | 4 of 4 passed |
| Nuxt | 3.97 s | +1.28 s95% interval 1.27 s to 1.38 s | 16 msOne visit measured | 4 of 4 passed |
| Astro | 3.74 s | +1.28 s95% interval 1.27 s to 1.29 s | Under 16 msOne visit measured | 4 of 4 passed |
| TanStack StartShown above | 4.11 s | +1.28 s95% interval 1.27 s to 1.37 s | 16 msOne visit measured | 4 of 4 passed |
When does Didomi load, and what does it cost the page?
Lab detail for engineers. All Core Web Vitals are here. The summary leaves some of them out.
When does Didomi start loading?
The banner was visible at 4.11 s. The published results do not show when Didomi started to load.
| Event | Time from navigation |
|---|---|
| First byte (TTFB) | 9 ms |
| First paint (FCP) | 252 ms |
| Banner visible | 4.11 s |
| Largest paint (LCP) | 4.61 s |
| CMP requested | |
| CMP loaded | |
| Consent state known |
How do page vitals compare with no consent manager?
Each row shows the value on the page with the consent manager. It also shows how far the value moved from the same page without one.
| Measure | With Didomi | Difference |
|---|---|---|
| TTFBTime to first byte | 9 ms | No measurable difference95% interval −3 ms to 5 ms |
| FCPFirst Contentful Paint | 252 ms | No measurable difference95% interval 0 ms to 16 ms |
| LCPLargest Contentful Paint | 4.61 s | +1.28 s95% interval 1.27 s to 1.37 s |
| CLSCumulative Layout Shift | 0.00 | No measurable difference95% interval: 0.00 |
| Primary content paintThe page’s main content, not the banner | 4.61 s | +1.28 s95% interval 1.27 s to 1.37 s |
What was the largest element on screen?
LCP times the largest element on screen. If that is the banner, LCP measures the banner instead of the page.
There is no LCP attribution for this profile and framework.
What happens after a visitor clicks Accept?
The screen responded to Accept in 16 ms.
| Event | Time from the click |
|---|---|
| Screen responds | 16 ms |
| Banner gone | |
| Consent applied | |
| Analytics active |
How much does it download?
Initial transfer happens before the page settles. Deferred transfer comes after.
| Measure | With Didomi | Difference |
|---|---|---|
| Initial transferBytes before the page settles | 843 KB | +253 KB95% interval 253 KB to 270 KB |
| Deferred transferBytes loaded later | Not compared | |
| RequestsAll requests | 13 | +6No interval reported |
| Third-party requestsRequests to other hosts | 6 | +6No interval reported |
Does it block the main thread?
Long tasks are stretches over 50 ms when the page cannot respond to taps or keys.
| Measure | With Didomi | Difference |
|---|---|---|
| Long-task timeBlocking time during load | 316 ms | +292 msNo interval reported |
What do returning visitors see?
A visitor who accepted on an earlier visit comes back. We check that the banner stays hidden.
- Banner stayed hidden
- Consent state known at
What was tested?
- Methodology
- cookiebench-v3.2.4
- Analysis
matrix-2026-10-11- Issues
- None recorded in this run
On desktop, it appeared in a median 466 ms, against 471 ms for the median of the 10 CMPs measured. On an emulated mid-tier phone, it appeared in a median 4.41 s, against 2.71 s for the median of the 10 CMPs measured.
On desktop it added no measurable delay to the main content. On an emulated mid-tier phone it delayed the main content by 1.28 s (95% interval 1.26 s to 1.29 s). Delay is the extra time before the main content appears. We compare Largest Contentful Paint on the same page, with and without a consent manager.
It passed 4 of 4 checks on desktop and on an emulated mid-tier phone. A check fails if a tracker runs, the page sets a cookie or data leaves the page before the visitor chooses.
Per vendor docs, Didomi supports IAB TCF, IAB GPP, Google Consent Mode v2, Google CMP certification and Global Privacy Control. Feature support comes from Didomi’s documentation. CookieBench did not test these features itself.
