{"id":1620,"date":"2026-10-19T12:15:00","date_gmt":"2026-10-19T10:15:00","guid":{"rendered":"https:\/\/www.sabatka.net\/cs\/?p=1620"},"modified":"2026-10-19T12:21:16","modified_gmt":"2026-10-19T10:21:16","slug":"gtm-container-optimization","status":"publish","type":"post","link":"https:\/\/www.sabatka.net\/cs\/gtm-container-optimization\/","title":{"rendered":"Optimalizace GTM: pro\u010d ji \u0159e\u0161it a jak na ni"},"content":{"rendered":"\n

V \u0159\u00edjnu 2026 p\u0159i\u0161el Google s novinkou: optimalizac\u00ed Google Tag Manageru (GTM)<\/a>. Ta slu\u010duje soubory, kter\u00e9 web mus\u00ed st\u00e1hnout pro m\u011b\u0159en\u00ed do r\u016fzn\u00fdch slu\u017eeb Googlu. Nov\u011b v\u00e1m tak sta\u010d\u00ed jen GTM, a web se proto na\u010dte rychleji. Optimalizace nav\u00edc p\u0159in\u00e1\u0161\u00ed bonus pro ochranu osobn\u00edch \u00fadaj\u016f: GTM m\u016f\u017eete nastavit tak, aby prohl\u00ed\u017ee\u010d n\u00e1v\u0161t\u011bvn\u00edka p\u0159ed souhlasem neposlal na servery Googlu v\u016fbec nic.<\/p>\n\n\n\n

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Chci odeb\u00edrat novinky<\/a><\/div>\n\n\n\n
Sd\u00edlet na LinkedIN<\/a><\/div>\n<\/div>\n\n\n\n

Pro\u010d optimalizaci GTM \u0159e\u0161it<\/h2>\n\n\n\n

GTM a rychlost webu<\/h3>\n\n\n\n

D\u0159\u00edv GTM pro ka\u017ed\u00fd m\u011b\u0159ic\u00ed k\u00f3d Googlu st\u00e1hl nav\u00edc samostatnou knihovnu (soubor gtag.js). Po optimalizaci tyto soubory odpadnou a v\u0161e obstar\u00e1 jedin\u00fd soubor GTM. Na sabatka.net<\/a>, kde m\u00e1m jedno GA4 a jedno Google Ads, to vy\u0161lo zhruba o 300 kB p\u0159enosu m\u00e9n\u011b a o dva soubory od Googlu m\u00e9n\u011b. P\u0159i v\u00edce m\u011b\u0159ic\u00edch k\u00f3dech \u00faspora roste, proto\u017ee ka\u017ed\u00fd gtag.js m\u00e1 zhruba 150\u2013180 kB p\u0159enosu.<\/p>\n\n\n\n

P\u0159enos je objem dat, kter\u00fd re\u00e1ln\u011b putuje po s\u00edti (soubory se pos\u00edlaj\u00ed zkomprimovan\u00e9):<\/p>\n\n\n\n

Soubor<\/th>P\u0159ed<\/th>Po<\/th><\/tr><\/thead>
gtm.js (soubor GTM)<\/td>~195 kB (odhad)<\/td>~231 kB<\/td><\/tr>
gtag.js pro GA4<\/td>181 kB<\/td>0<\/td><\/tr>
gtag.js pro Google Ads<\/td>155 kB<\/td>0<\/td><\/tr>
P\u0159enos celkem<\/strong><\/td>~530 kB (odhad)<\/strong><\/td>~231 kB<\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Pro specialisty: nekomprimovan\u011b to bylo 1 610 kB a je 742 kB. Samotn\u00fd gtm.js vyrostl z 629 na 742 kB, proto\u017ee do n\u011bj p\u0159ibylo nastaven\u00ed GA4 a Ads. Souvislosti najdete v \u010dl\u00e1nku GTM a rychlost webu<\/a>.<\/p>\n\n\n\n

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\"V\u011bd\u011bli<\/figure>\n<\/div>\n\n\n\n
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V\u011bdeck\u00e1 pozn\u00e1mka<\/strong><\/strong><\/h3>\n\n\n\n

Je to jako Occamova b\u0159itva<\/a>: nejjednodu\u0161\u0161\u00ed \u0159e\u0161en\u00ed b\u00fdv\u00e1 nejlep\u0161\u00ed, tedy jeden soubor m\u00edsto t\u0159\u00ed.<\/p>\n<\/div>\n<\/div>\n\n\n\n

GTM a GDPR<\/h3>\n\n\n\n

Spousta web\u016f dnes pou\u017e\u00edv\u00e1 skripty Googlu v re\u017eimu Advanced Consent Mode<\/a>: bez souhlasu sice neukl\u00e1daj\u00ed cookies, ale data do m\u011b\u0159ic\u00edch n\u00e1stroj\u016f pos\u00edlaj\u00ed d\u00e1l (takzvan\u00e9 anonymn\u00ed pingy).<\/p>\n\n\n\n

Kdykoli ale prohl\u00ed\u017ee\u010d n\u00e1v\u0161t\u011bvn\u00edka st\u00e1hne soubor nebo po\u0161le po\u017eadavek na dom\u00e9nu Googlu, Google dostane jeho IP adresu (adresu, podle kter\u00e9 jde n\u00e1v\u0161t\u011bvn\u00edka v s\u00edti dohledat) a \u00fadaje o za\u0159\u00edzen\u00ed. I kv\u016fli tomu n\u011bmeck\u00fd spr\u00e1vn\u00ed soud v Hannoveru v b\u0159eznu 2025 v prvoinstan\u010dn\u00edm rozsudku rozhodl, \u017ee nasazen\u00ed GTM vy\u017eaduje souhlas (rozbor najdete v \u010dl\u00e1nku GTM v rozporu s GDPR<\/a>).<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Pokud chcete zachovat anonymn\u00ed pingy pro analytiku a nevad\u00ed v\u00e1m p\u0159ij\u00edt o remarketingov\u00e1 data od lid\u00ed bez souhlasu (remarketing je c\u00edlen\u00ed reklamy na lidi, kte\u0159\u00ed u\u017e web nav\u0161t\u00edvili), m\u016f\u017ee b\u00fdt \u0159e\u0161en\u00edm kombinace dvou v\u011bc\u00ed:<\/p>\n\n\n\n

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  1. Server-side GTM<\/strong>
    Server-side GTM<\/a> (sGTM) je v\u00e1\u0161 vlastn\u00ed m\u011b\u0159ic\u00ed server, p\u0159es kter\u00fd data projdou d\u0159\u00edv, ne\u017e odejdou k Googlu. Z n\u011bj se bude stahovat GTM a na n\u011bj bude GA4 pos\u00edlat data. Je\u0161t\u011b p\u0159ed sGTM je ide\u00e1ln\u00ed z po\u017eadavku odstranit p\u016fvodn\u00ed IP adresu, p\u0159\u00edpadn\u011b dal\u0161\u00ed \u00fadaje o n\u00e1v\u0161t\u011bvn\u00edkovi.<\/li>\n\n\n\n
  2. Optimalizace a blokov\u00e1n\u00ed reklamn\u00edch dat bez souhlasu<\/strong>
    Remarketingov\u00e9 k\u00f3dy Google Ads nejde odklonit jen na v\u00e1\u0161 server. I p\u0159i server-side nastaven\u00ed pot\u0159ebuj\u00ed, aby prohl\u00ed\u017ee\u010d kontaktoval dom\u00e9ny Googlu, proto\u017ee tam m\u00e1 Google ulo\u017een\u00e9 sv\u00e9 cookies. Do ud\u011blen\u00ed souhlasu je proto mus\u00edte vypnout.<\/li>\n<\/ol>\n\n\n\n

    Prohl\u00ed\u017ee\u010d n\u00e1v\u0161t\u011bvn\u00edka pak p\u0159ed souhlasem se servery Googlu nekomunikuje v\u016fbec a co z va\u0161eho serveru odejde d\u00e1l, ur\u010dujete sami. Pozor: souhlas pro samotn\u00e9 m\u011b\u0159en\u00ed pot\u0159ebujete d\u00e1l, se v\u0161\u00edm, co k tomu pat\u0159\u00ed.<\/p>\n\n\n\n

    Soud \u0159e\u0161il GTM na\u010d\u00edtan\u00e9 od Googlu. Zda obstoj\u00ed na\u010dten\u00ed vlastn\u00edho gtm.js p\u0159ed souhlasem, ne\u0159e\u0161il.<\/p>\n\n\n\n

    Upozorn\u011bn\u00ed: tento \u010dl\u00e1nek neberte jako pr\u00e1vn\u00ed radu. Nastaven\u00ed proberte s vlastn\u00edm pr\u00e1vn\u00edkem.<\/p>\n\n\n\n

    Co optimalizace GTM m\u011bn\u00ed<\/h2>\n\n\n\n

    Google ji ofici\u00e1ln\u011b popisuje jako Optimize your Google Tag Manager container<\/a> (release note z 12. 10. 2026). Kontejner (bal\u00edk va\u0161ich tag\u016f a nastaven\u00ed v GTM) se s\u00e1m st\u00e1v\u00e1 Google tagem. Dosavadn\u00ed typ tagu Google tag, kter\u00fd na\u010d\u00edtal vlastn\u00ed gtag.js, je te\u010f ozna\u010den\u00fd jako \u201elegacy\u201c, tedy star\u0161\u00ed typ, kter\u00fd d\u00e1l funguje, ale stahuje vlastn\u00ed gtag.js. GA4 a Google Ads se ke kontejneru p\u0159idaj\u00ed jako \u201eGoogle destinations\u201c, tedy c\u00edle, kam GTM data pos\u00edl\u00e1. Ka\u017ed\u00e1 destinace m\u00e1 vlastn\u00ed destination tag, kter\u00fd data ode\u0161le bez dal\u0161\u00edho souboru.<\/p>\n\n\n\n

    Co se m\u011bn\u00ed v rozhran\u00ed:<\/p>\n\n\n\n

    Settings<\/strong> v lev\u00e9m menu: seznam destinac\u00ed se sloupcem Optimized (Yes\/No) a nastaven\u00ed spole\u010dn\u00e1 pro v\u0161echny destinace. Nap\u0159\u00edklad automatic event detection (automatick\u00e9 sledov\u00e1n\u00ed scrollu, odchoz\u00edch klik\u016f a formul\u00e1\u0159\u016f) nebo Manage data transmission (co se sm\u00ed odeslat bez souhlasu).<\/p>\n\n\n\n

    \"\"<\/figure>\n\n\n\n

    Overview > Container quality<\/strong> s mapou, kter\u00e1 ukazuje, co do jak\u00e9 destinace te\u010de.<\/p>\n\n\n\n

    \"\"<\/figure>\n\n\n\n

    V Preview<\/strong> (testovac\u00ed re\u017eim, kter\u00fd uk\u00e1\u017ee, co by se na webu spustilo, ne\u017e zm\u011bny publikujete) nov\u00e1 z\u00e1lo\u017eka Hits Sent, tedy p\u0159ehled, co kam ode\u0161lo.<\/p>\n\n\n\n

    \"\"<\/figure>\n\n\n\n

    Technick\u00e9 nastaven\u00ed<\/h2>\n\n\n\n

    Projd\u011bte pr\u016fvodce optimalizac\u00ed<\/p>\n\n\n\n