Web.Contents

What a web address answers, as a binary: a file to read with Csv.Document, Json.Document or another reader.

Group: Files and documents. Power Query M has it too: a query that uses it is written as in Power BI.

Syntax

Web.Contents(url as text, optional options as nullable record) as binary

Parameter	Type	Description
`url`	text	The address, http:// or https://.
`options`	nullable record optional	RelativePath, Query, Headers, Content, ApiKeyName and ManualStatusHandling.

Returns

binary. The answer's body, fetched when something reads it.

Remarks

RelativePath is added to the address after a slash; Query's fields are added as ?name=value&..., encoded for an address. Headers are sent with the request. Content (text or binary) makes the request a POST with that body.
A key belongs in the sign-in, never in the query's M. The studio asks for the sign-in (Anonymous, Web API key or Basic) the first time it reads the address; a Web API key goes in a header, or in the query value that ApiKeyName names.
An answer of 400 or more is an error, unless ManualStatusHandling lists its status: then the body is given, and Value.Metadata of it has Response.Status.
The request goes out when the bytes are read, not when Web.Contents runs: a try around Web.Contents alone doesn't see a failed request; put it around the step that reads the bytes.
On OpenBI Server, the server's web guard checks every address and every redirect before it is read.

Examples

A CSV file on the web

Csv.Document(Web.Contents("https://data.example.com/exports/prices.csv"))

Result: not shown here: it reads a web address, which the docs' build doesn't.

A web API with a path, a query and a header

The request goes to https://api.example.com/v1/orders?status=open.

Json.Document(Web.Contents("https://api.example.com", [
    RelativePath = "v1/orders",
    Query = [status = "open"],
    Headers = [Accept = "application/json"]
]))

Result: not shown here: it calls a web API, which the docs' build doesn't.

Nothing is fetched until the bytes are needed

Web.Contents("https://data.example.com/exports/prices.csv") is binary

true

The value is a binary at once; the address is read only when a reader such as Csv.Document uses it.

Csv.Document, Json.Document, Value.Metadata, Binary.Buffer, OData.Feed.

Last updated 8 November 2026 · OpenBI Studio 0.3.79