Social media image sizes, API

Every size in one table, each with its source and whether the network itself states it, plus a resizer that crops your image to any of them without uploading it.

• Endpoint: GET https://postboost.co/app/api/tools/social-media-image-sizes (operationId getImageSizes)
• Web tool: postboost.co/tools/social-media-image-sizes
• Token: optional (limits)
• MCP: tool get-image-sizes on https://postboost.co/mcp/tools

Request

Query parameter	Type	Default	Description
network	string		Network key, e.g. instagram. Omit it for every network; an unknown key is a 422 that lists the allowed ones.

Call it

curl

curl 'https://postboost.co/app/api/tools/social-media-image-sizes?network=bluesky'

Python

from postboost import ApiClient, Configuration
from postboost.api.free_tools_api import FreeToolsApi

with ApiClient(Configuration()) as client:
    api = FreeToolsApi(client)
    result = api.get_image_sizes(network='bluesky')
    print(result.to_dict())

Node.js

import { FreeToolsApi } from 'postboost';

const api = new FreeToolsApi();
const { body } = await api.getImageSizes('bluesky');
console.log(body);

PHP

use PostBoostClient\Api\FreeToolsApi;

$api = new FreeToolsApi(new GuzzleHttp\Client());
$result = $api->getImageSizes("bluesky");
echo $result;

Go

import (
    "context"
    "fmt"

    postboost "github.com/postboost-co/postboost-go"
)

client := postboost.NewAPIClient(postboost.NewConfiguration())
result, _, err := client.FreeToolsAPI.GetImageSizes(context.Background()).Network("bluesky").Execute()
fmt.Println(result, err)

Ruby

require 'postboost'

api = PostBoost::FreeToolsApi.new
result = api.get_image_sizes(network: 'bluesky')
puts result.to_hash

Java

import com.postboost.ApiClient;
import com.postboost.api.FreeToolsApi;
import com.postboost.model.FreeToolGetImageSizesResponse;

FreeToolsApi api = new FreeToolsApi(new ApiClient());
FreeToolGetImageSizesResponse result = api.getImageSizes("bluesky");
System.out.println(result.toJson());

C#

using PostBoost.Client.Api;
using PostBoost.Client.Client;

var api = new FreeToolsApi(new Configuration());
var result = await api.GetImageSizesAsync("bluesky");
Console.WriteLine(result.ToJson());

Rust

use postboost::apis::configuration::Configuration;
use postboost::apis::free_tools_api;

let config = Configuration::new();
let result = free_tools_api::get_image_sizes(&config, Some("bluesky")).await?;
println!("{:?}", result);

CLI

./postboost-cli getImageSizes network='bluesky'

With a token, send Authorization: Bearer YOUR_API_TOKEN as a default header (how, per SDK).

Response

{
    "sizes": [
        {
            "network": "Bluesky",
            "network_key": "bluesky",
            "placement": "Profile photo",
            "format_key": "profile-photo",
            "size": "1000×1000",
            "width": 1000,
            "height": 1000,
            "ratio": "1:1",
            "limits": "Post images are stored at 1000 px on the long side",
            "basis": "common practice",
            "source": "Hootsuite"
        },
        {
            "network": "Bluesky",
            "network_key": "bluesky",
            "placement": "Banner",
            "format_key": "banner",
            "size": "3000×1000",
            "width": 3000,
            "height": 1000,
            "ratio": "3:1",
            "limits": "",
            "basis": "common practice",
            "source": "Hootsuite"
        }
    ],
    "last_verified": "2026-10-13",
    "sources": [
        {
            "label": "Sprout Social, social media image sizes guide (updated 2026-05-11)",
            "url": "https://sproutsocial.com/insights/social-media-image-sizes-guide/"
        },
        {
            "label": "Hootsuite, social media image sizes guide (2026-10-01)",
            "url": "https://blog.hootsuite.com/social-media-image-sizes-guide/"
        }
    ]
}

With MCP

Connect https://postboost.co/mcp/tools (setup) and ask, for example: Get social media image sizes per network, each with its source with the PostBoost get-image-sizes tool.

Errors

Status	When
401	The Authorization header holds an invalid token. Leave it out to call as a guest.
413	The JSON body is larger than 128 KB.
422	A field is invalid; the body lists the errors per field.
429	A limit is reached; see limits.