How good is Sanity at localization?

How does Sanity handle localization?

Sanity handles localization by storing the language as a field value, so translated content is ordinary structured content rather than a built-in locale layer (Sanity Docs, Localization, October 2026). You choose a model per document type, and Sanity maintains two plugins that make each model workable in Sanity Studio: one for translated documents and one for translated fields. Both can run in the same project (Sanity Docs, Localization).

Locales cost nothing extra. Sanity's pricing page lists unlimited locales on Free, Growth and Enterprise and says it doesn't charge for locales, as long as you stay within the unique attributes included per dataset (as of October 2026, Sanity pricing). That condition is the catch: you pay for localization in quota, either attributes or documents, depending on the model.

Fallbacks are yours to write. A query falls back to a base language with the coalesce() function in GROQ (Graph-Relational Object Queries), so a missing translation shows the default copy only if a developer wrote it that way (Sanity Docs, Localization). Our overall Sanity review puts this trade, flexibility for setup work, in context.

How does Deploi score Sanity on localization?

Deploi scores Sanity 4 out of 5 on localization, the rounded mean of six criteria. The score rests on Sanity's documentation, its pricing page and the translation vendors' own connector pages. Sanity scores highest on modeling freedom and locale cost, and lowest on limits at scale and setup effort. Translation tooling sits at 4, because AI Assist, the Translate action and translation management system (TMS) connectors each cover part of the job.

Should you localize by document or by field in Sanity?

Localize by document when a language publishes on its own schedule or carries long-form text, and by field when short shared values must stay in sync across languages. Sanity's localization guide draws the same line: field-level "requires you to publish content in all languages simultaneously," while document-level "lets you publish each language version independently" (Sanity Docs, Localization, October 2026). You can use both in one project, so decide per document type, and plan the localization workflow around the slowest market.

Two pitfalls to plan for. Both plugins changed how they store the language in March 2026, so older queries that filter on the item key break after the upgrade (Sanity Docs, Localization). And flipping many document-level locales live in one moment is what Content Releases is built for, an Enterprise add-on (Content Releases user guide, October 2026).

How does translation work in Sanity?

Translation in Sanity runs through one of three routes: AI Assist inside Sanity Studio, the Translate action called from code, or a translation management system (TMS) connector. AI Assist translates whole documents or fields on the Growth plan and up, and whole-document translation overwrites the current values, so editors copy the document first and review the result (AI Assist translation docs, October 2026). The Translate action in Agent Actions takes a style guide and protected phrases from code, but Sanity marks it experimental (Translate quick start, October 2026; Sanity's AI translation guide).

Your TMS connector decides your model more than Sanity does, because several connectors support only document-level translation:

See Sanity with Smartling and Sanity with Phrase for setup.

Which limits bite when you localize Sanity at scale?

Two quotas bite: unique attributes per dataset, which language objects multiply, and documents, which document-level translation multiplies. A unique attribute is a distinct content path and data type in a dataset. A dataset tops out at 10,000 attributes on Growth, and the attribute guide says moving to Enterprise doesn't raise it and no pay-as-you-go option exists (Attribute limit guide, October 2026). Wrapping each field in a language object "multiplies the number of attributes by the number of languages added" (Attribute limit guide), so that pattern hits the ceiling first, while arrays and separate documents don't.

Growth includes 25,000 documents, and $299 a month extends that to 50,000 in total (Sanity pricing, October 2026); drafts and plugin-created documents count (Technical limits). 2,000 articles in 10 languages at document level is 20,000 documents plus 2,000 linked metadata documents, or 22,000 before drafts (Deploi arithmetic from the figures above). The same content at field level is 2,000 documents. Check the document limits before you pick.

What do you build yourself in Sanity that Contentful's built-in locales provide?

You build the fallback locales and the per-locale publishing workflow, because Contentful builds locales into the platform and Sanity leaves them to your content model. Contentful's field-level pattern duplicates the fields of an entry for each locale and configures fallbacks (Contentful Help Center, October 2026). Its locale-based publishing, which publishes one locale on its own, is an Enterprise-level feature of Enterprise Spaces (Contentful pricing; Contentful locale-based publishing, October 2026). Sanity matches that with document-level translation and fallbacks written into queries.

Contentful also counts locales against the plan: 2 on Free and 3 on Lite, which lists at $300 a month on Contentful's pricing page (October 2026), with a technical ceiling of 500 per environment (Contentful pricing; Contentful technical limits). Sanity vs Contentful covers price.