Flat / Spreadsheet hosting
Spreadsheet hosting: share workbook data with a link
Publish a spreadsheet from your browser or the CLI. Let readers inspect the saved data online and download the original workbook for their own analysis.
Checking your upload limits... · Public · Limits
Drop your Spreadsheet files here
or choose them from your device.
Select Spreadsheet filesWhat readers see at your Spreadsheet link
Flat displays CSV, XLSX, XLS, and ODS data in a scrolling grid. Workbooks with several sheets have sheet tabs. The example shows a project-cost workbook with a separate Notes sheet.
The preview shows data and basic number formatting. Formulas do not run, but stored results can appear. Charts, macros, and exact spreadsheet styling are not part of this reading view.
A single file opens in the viewer. Several files open in the explorer, where readers can choose a file. Public links need no Flat account. Original downloads remain available if a preview cannot load.
The main link opens Flat's viewer. The exact path /project-costs.xlsx serves the original file, without changing its contents.
How to upload Spreadsheet files and get a link
Prepare your file
Recalculate and save your workbook before uploading. Use clear column headings and sheet names. Check saved formula values and external-data dependencies in your spreadsheet application.
Choose CSV for one table, XLSX for a current Excel workbook, XLS for a legacy requirement, or ODS for an OpenDocument workbook. Publish a PDF companion if the report needs exact page layout or charts.
Publish from your browser or terminal
In your browserGo to uploaderDrop, publish, copy the link.
Drop your finished files into the uploader above, or select them from your device. Enter your email if signed out, then choose "Publish files".
Selected files need unique names and publish at the top level. Use the CLI for folders; the browser uploader does not accept folders or extract ZIPs.
TerminalNode.js 20+One command. Files or folders.
npx -y @getflat/cli deploy ./project-costs.xlsxReplace the example path with your file. Pass a folder to publish related files with their relative paths intact. The CLI prints the published URL.
Check before sharing
Check each sheet, dates, and important numeric values in the preview. Download the original when verifying features that belong to your spreadsheet application.
Signed-out uploads expire after 1 hour by default. Sign in before expiry to keep them online, or sign in before publishing for no default expiry.
What you can share with Spreadsheet hosting
Report snapshots
Send the saved figures from a reporting period. A version link keeps that upload available without changing when you publish the next report.
Data handoffs
Let a recipient inspect table headers and sample values before downloading the file into their own analysis or import tool.
Keep a version, or keep an address.
Share this version
Every upload gets its own link. Publishing revised files creates a new link and leaves the earlier version unchanged. Use the version link when someone needs to review a specific upload.
Update files at one address
Use a named onflat.page address or your own domain. Sign in, then publish with the CLI using --domain. Publish revised files with the same domain to point that address to the new upload.
Named addresses are included on Free. Adding your own domain requires a paid plan. The browser uploader does not set up or repoint these addresses.
Spreadsheet hosting questions
Is hosting free, and what are the limits?
Yes. Signed-in Free includes 5 MiB per upload, 1 GiB of storage, and 5 GiB of monthly transfer, with no default expiry. The per-upload limit covers all files in that upload. Paid plans raise these limits.
Do readers need a Flat account?
No. Public links open without a Flat account. Anyone with the link can open the uploaded files. Password-protected links also require the visitor password.
Can I password-protect my upload?
Yes. Password protection is available on every plan. Add --password YOUR_PASSWORD to your CLI deploy command. It protects access to the upload and its files, but does not prevent someone with access from saving a copy. The browser uploader creates public uploads.
Can I replace files without changing the link?
A version link always refers to its original upload. For same-address updates, use a named address or your own domain. Publish revised files with the same --domain value in the CLI to point that address to the new upload.
What happens when an upload expires?
Flat stops serving it. An expired upload cannot be recovered. Signed-out uploads expire after 1 hour by default. For browser uploads, use the sign-in link shown after publishing. For CLI uploads, run npx -y @getflat/cli login. Complete sign-in before expiry to keep the upload online. If you chose a shorter expiry in the CLI, that deadline stays in place.
Which spreadsheet format should I upload?
Use CSV for a single table. Use XLSX or ODS when you need several sheets and an editable workbook download. Keep XLS when an older system requires it. The cards below explain each format.
Is this an online spreadsheet editor?
No. The grid is read-only. It does not provide cell editing, filters, live calculations, or collaboration. Readers can download the original and use their own spreadsheet software.
Does the preview hide sheets or protect workbook data?
Do not use workbook hiding or sheet protection as an access boundary for published data. Prepare a separate workbook containing only the data you intend to share. Readers with access can download the complete uploaded file.
How large can an upload be?
Upload allowances depend on your plan and cover all files in the upload. Compare current plan limits. Preview availability also depends on format and processing support. The original file remains available to download if a preview is unavailable.
Can I embed the viewer on another website?
Flat's generated viewer cannot be embedded in an iframe and keeps Flat branding on every plan. Link to the viewer for reading or to the exact file URL for the original.
Choose your spreadsheet format
Find the guide for your spreadsheet file.
Give your Spreadsheet files a link.
Publish your file, check the preview, and share the URL.
Publish filesFree to start · View pricing