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<div class="z-2 w-full flex-none lg:flex lg:h-dvh lg:w-[270px] lg:flex-col 2xl:w-[300px] false"><div class="shadow-alternate flex h-auto w-full items-center rounded-b-xl border-b bg-white py-2 text-lg leading-tight lg:hidden"> <div class="flex flex-1 cursor-pointer flex-col justify-center self-stretch pl-6"><p class="text-sm text-gray-400 first-letter:capitalize">Tokenizers documentation </p> <div class="mr-2 flex items-center"><p class="font-semibold">Tokenizers</p> <svg class="text-xl false" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 24 24"><path d="M16.293 9.293L12 13.586L7.707 9.293l-1.414 1.414L12 16.414l5.707-5.707z" fill="currentColor"></path></svg></div></div> <button class="hover:shadow-alternate group ml-auto mr-6 inline-flex flex-none cursor-pointer rounded-xl border p-2"><svg class="text-gray-500 group-hover:text-gray-700" 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<link href="/docs/tokenizers/v0.20.3/en/_app/immutable/assets/0.e3b0c442.css" rel="modulepreload"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/entry/start.8f1a63aa.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/chunks/scheduler.9f522b10.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/chunks/singletons.edbeb51b.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/chunks/index.eb046c14.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/chunks/paths.166d39bb.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/entry/app.12072cfd.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/chunks/index.192f26f8.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/nodes/0.9bbd9d68.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/chunks/each.e59479a4.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/nodes/15.3f9e4a7a.js"> <link rel="modulepreload" href="/docs/tokenizers/v0.20.3/en/_app/immutable/chunks/EditOnGithub.6d5e7de4.js"><meta name="hf:doc:metadata" content="{"title":"Tokenizers","local":"tokenizers","sections":[],"depth":1}"> <p></p> <h1 class="relative group"><a id="tokenizers" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#tokenizers"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Tokenizers</span></h1> <p data-svelte-h="svelte-hqcehv">Fast State-of-the-art tokenizers, optimized for both research and production</p> <p data-svelte-h="svelte-ydrho4"><a href="https://github.com/huggingface/tokenizers" rel="nofollow">🤗 Tokenizers</a> provides an implementation of today’s most used tokenizers, with a focus on performance and versatility. These tokenizers are also used in <a href="https://github.com/huggingface/transformers" rel="nofollow">🤗 Transformers</a>.</p> <h1 class="relative group"><a id="main-features" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#main-features"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Main features:</span></h1> <ul data-svelte-h="svelte-1k61qc"><li>Train new vocabularies and tokenize, using today’s most used tokenizers.</li> <li>Extremely fast (both training and tokenization), thanks to the Rust implementation. Takes less than 20 seconds to tokenize a GB of text on a server’s CPU.</li> <li>Easy to use, but also extremely versatile.</li> <li>Designed for both research and production.</li> <li>Full alignment tracking. Even with destructive normalization, it’s always possible to get the part of the original sentence that corresponds to any token.</li> <li>Does all the pre-processing: Truncation, Padding, add the special tokens your model needs.</li></ul> <a class="!text-gray-400 !no-underline text-sm flex items-center not-prose mt-4" href="https://github.com/huggingface/tokenizers/blob/main/docs/source-doc-builder/index.mdx" target="_blank"><span data-svelte-h="svelte-1kd6by1"><</span> <span data-svelte-h="svelte-x0xyl0">></span> <span data-svelte-h="svelte-1dajgef"><span class="underline ml-1.5">Update</span> on GitHub</span></a> <p></p> <script> { __sveltekit_xjj08i = { assets: "/docs/tokenizers/v0.20.3/en", base: "/docs/tokenizers/v0.20.3/en", env: {} }; const element = document.currentScript.parentElement; const data = [null,null]; Promise.all([ import("/docs/tokenizers/v0.20.3/en/_app/immutable/entry/start.8f1a63aa.js"), import("/docs/tokenizers/v0.20.3/en/_app/immutable/entry/app.12072cfd.js") ]).then(([kit, app]) => { kit.start(app, element, { node_ids: [0, 15], data, form: null, error: null }); }); } </script> </div> <div class="SVELTE_HYDRATER contents" data-target="DocFooterNav" data-props="{"classNames":"mx-auto mt-16 flex max-w-4xl items-center pb-8 font-sans font-medium leading-6 xl:mt-32","chapterNext":{"title":"Quicktour","isExpanded":true,"id":"quicktour","url":"/docs/tokenizers/quicktour"},"isCourse":false,"isLoggedIn":false}"><div class="mx-auto mt-16 flex max-w-4xl items-center pb-8 font-sans font-medium leading-6 xl:mt-32"> <a href="/docs/tokenizers/quicktour" class="ml-auto flex transform items-center text-right text-gray-600 transition-all hover:translate-x-px hover:text-gray-900 dark:hover:text-gray-300">Quicktour<span class="ml-2 translate-y-px">→</span></a></div></div></div></div> <div class="sticky top-0 self-start"><div class="SVELTE_HYDRATER contents" data-target="SubSideMenu" data-props="{"chapter":{"title":"Tokenizers","isExpanded":true,"id":"tokenizers","url":"#tokenizers","sections":[]}}"> <nav class="hidden h-dvh w-[270px] flex-none flex-col space-y-3 overflow-y-auto break-words border-l pb-16 pl-6 pr-10 pt-24 text-sm lg:flex 2xl:w-[305px]"> <a href="#tokenizers" class=" text-gray-400 transform hover:translate-x-px hover:text-gray-700 dark:hover:text-gray-300" id="nav-tokenizers"><wbr>Tokenizers</a> </nav></div></div></div> <div id="doc-footer"></div></main> </div> <script> import("\/front\/build\/kube-aa0622c\/index.js"); window.moonSha = "kube-aa0622c\/"; window.__hf_deferred = {}; </script>  <script> if (["hf.co", "huggingface.co"].includes(window.location.hostname)) { const script = document.createElement("script"); script.src = "https://js.stripe.com/v3/"; script.async = true; document.head.appendChild(script); } </script> </body> </html>