---
title: "read: compare"
description: "two brands, a question from the closed list of comparisons to two summaries over one structure, each with its coverage"
section: reference
address: /reference/read/compare
contract: 0476e35e6e275db5
---
# read: compare
two brands, a question from the closed list of comparisons to two summaries over one structure, each with its coverage
[figure: The caller sends CompareInput to /v1/read/compare. The platform returns a card whose body is Comparison.]
POST/v1/read/compare
Compare two brands. The call needs the brand rung under a token with the read grant, and it is served by the platform.
The route takes [CompareInput](/concepts/compareinput) and returns a card whose body is [Comparison](/concepts/comparison).
## Request body
The request body is [CompareInput](/concepts/compareinput).
| field | type | required | note |
|---|---|---|---|
| `first` | `id` | yes | |
| `second` | `id` | yes | |
| `question` | [ComparisonQuestion](/concepts/comparisonquestion) | yes | |
## Response
The route returns a card whose body is [Comparison](/concepts/comparison). Every card ends with a foot that states the basis of each number, the scope of the call, and the time when the facts were true.
## Headers
| header | required | meaning |
|---|---|---|
| `Scale-Scope` | yes | the scope the call runs in: tenant/, then /brand/, then /strategy/ |
| `Scale-As-True-On` | no | the date the facts must have been true on; defaults to now |
| `Scale-As-Known-On` | no | the date the facts must have been known on; defaults to now |
| `Scale-Key` | no | for a change, the key made from the input; a repeat under the same key returns the unit held and writes nothing |
A caller needs the brand rung and a token with the read grant. The platform serves this route.
## Example
The example sends the smallest body that CompareInput allows. The build validates it against the schema of CompareInput.
Example
```sh
curl -X POST https://api.scaleintelligence.co/v1/read/compare \
-H "Scale-Key: $SCALE_KEY" -H "Scale-Scope: tenant/" \
-H "content-type: application/json" \
-d '{ "first": "…", "second": "…", "question": "…" }'
```
```typescript
import { client } from "@scale/sdk";
const answer = await client.read.compare({
"first": "…",
"second": "…",
"question": "…"
});
// answer.body is a Comparison. answer.foot holds the basis, the scope and the time.
```
```python
import requests
answer = requests.post("https://api.scaleintelligence.co/v1/read/compare",
headers={"Scale-Key": KEY, "Scale-Scope": "tenant/"},
json={
"first": "…",
"second": "…",
"question": "…"
}).json()
```
```rust
let answer: Card = client.post("https://api.scaleintelligence.co/v1/read/compare")
.header("Scale-Key", key).header("Scale-Scope", "tenant/")
.json(&CompareInput { /* the fields of the page */ }).send().await?.json().await?;
```