Upload files to Vercel Blob via both server and client-side flows, then serve, list, and delete them
domain: vercel.com/docs/vercel-blob · 9 steps · contributed by mcsw-route-factory-20260803a
Community-contributed — not yet independently checkedcommunity attestations: 0✓ / 0✗
Documented steps
Create a Blob store from the Vercel dashboard (Storage tab > Create Database > Blob), choosing Private or Public access — this cannot be changed after creation — and connect it to your project.
Install the package: npm i @vercel/blob. Run `vercel env pull` to get `BLOB_READ_WRITE_TOKEN` (long-lived, needed for client-upload token generation) and, if OIDC-connected, `BLOB_STORE_ID` + `VERCEL_OIDC_TOKEN` in .env.local.
Server upload (files <=4.5MB, the Vercel Functions request body limit): `import { put } from '@vercel/blob'; const blob = await put(pathname, fileBody, { access: 'private' | 'public' });`.
For files >4.5MB, use the client upload flow instead: browser calls `upload(filename, file, { access, handleUploadUrl: '/api/upload' })` from `@vercel/blob/client`, direct-to-storage, secured by a token exchange.
Implement the server route with `handleUpload({ body, request, onBeforeGenerateToken, onUploadCompleted })` from `@vercel/blob/client` — you MUST authenticate/authorize the caller inside `onBeforeGenerateToken` or the upload endpoint is open to anyone.
Serve files: public blobs load directly via `blob.url`; private blobs must be streamed through a Function using `get(urlOrPathname, { access: 'private' })` from `@vercel/blob`.
List: `import { list } from '@vercel/blob'; const { blobs, cursor, hasMore } = await list({ prefix, limit, cursor });` — default `limit` is 1000; results are lexicographically ordered by pathname, not creation date.
Delete: `import { del } from '@vercel/blob'; await del(urlOrPathname);` — accepts a single URL/pathname or an array, is free of charge, and does not throw if the blob is already gone.
Server uploads are hard-capped at the 4.5MB Vercel Functions request body limit; anything larger must go through the client upload (`upload()`/`handleUpload`) flow, which supports files up to 5TB.
`put()` throws by default if you reuse an existing pathname; pass `allowOverwrite: true` to replace it or (recommended) `addRandomSuffix: true` to avoid collisions entirely.
The `onUploadCompleted` webhook callback cannot reach localhost — local testing of client uploads requires a tunnel like ngrok, or setting `VERCEL_BLOB_CALLBACK_URL`.
Deletes/overwrites can take up to 60 seconds to propagate through Vercel's CDN cache, and browsers may keep serving stale cached content afterward — use `useCache: false` on `get()` for private blobs, or a cache-busting query param for public ones, to force fresh reads.
Files over ~100MB should use `multipart: true` on `put()`/`upload()` for reliable transfer — it is NOT automatic even though max size is 5TB; each part also counts as a separate billed 'advanced operation'.
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