BrowserSolver .NET SDK

The official .NET SDK for the BrowserSolver web unlocker API.

Unlock, render, crawl and screenshot any website — anti-bot bypass and technology detection through one API.

The SDK exposes 9 typed async methods, one per documented endpoint (with required properties checked at compile time), plus a generic RequestAsync.

Requirements

• .NET 8 or newer

Installation

dotnet add package BrowserSolver

Get your API key

Sign up for BrowserSolver or sign in, then copy your API key from the dashboard. new BrowserSolverClient() reads the BROWSERSOLVER_API_KEY environment variable.

Quick start

using BrowserSolver;

using var client = new BrowserSolverClient();
var response = await client.WebsiteWebunlockerAsync(new WebsiteWebunlockerParams { Query = "https://example.com" });
Console.WriteLine(response.Json);

Parameter classes mirror the API reference. Use response.Deserialize<MyType>() to map the JSON onto your own types.

Binary responses

Endpoints that return a file (image, PDF…) give you the bytes; IsJson tells both cases apart:

var response = await client.WebsiteScreenshotAsync(new WebsiteScreenshotParams { Url = "https://example.com", Format = "png" });
if (!response.IsJson)
{
    await File.WriteAllBytesAsync("screenshot.png", response.Bytes);
}

Async jobs

Any call accepts is_async: true (useful past the 60-second server limit): the response is then a job_id. WaitForJobAsync polls GET /v1/jobs/{id} until a terminal status (CompletedJob, Error, NotFound, BadRequest):

var submitted = await client.WebsiteWebunlockerAsync(new WebsiteWebunlockerParams { Query = "https://example.com", IsAsync = true });
var job = await client.WaitForJobAsync(
    submitted.Json.GetProperty("job_id").GetString()!,
    onProgress: j => Console.WriteLine($"{j.GetProperty("status")} {j.GetProperty("progress")}%"));

GET or POST

Methods use GET when the endpoint supports it (query string). POST sends the same parameters as JSON:

await client.WebsiteCrawlerAsync(new WebsiteCrawlerParams { Query = "https://books.toscrape.com/" }, new RequestOptions { Method = "POST" });

Any endpoint

var response = await client.RequestAsync("GET", "/v1/usage");

Errors

try
{
    await client.WebsiteWebunlockerAsync(new WebsiteWebunlockerParams { Query = "https://example.com" });
}
catch (BrowserSolverApiException exception)
{
    Console.Error.WriteLine($"{exception.StatusCode}: {exception.Message}");
}

Exception	When
BrowserSolverConfigurationException	Missing API key, invalid options or unsupported method.
BrowserSolverSerializationException	A required parameter is missing or a value can't be sent.
BrowserSolverTransportException	Network failure or timeout.
BrowserSolverApiException	Non-2xx status (StatusCode, ErrorMessage, ResponseBody, RawResponse).
BrowserSolverResponseDecodingException	A success response could not be decoded.

All of them derive from BrowserSolverException. Caller cancellation surfaces as OperationCanceledException.

Retries

Requests are retried up to 3 times after a network error, a 408, 500, 502, 503 or 504, or a rate limit — which the API returns as 401 (or 429) with a Rate limit exceeded message. Per-key quota errors (…: quota daily) are not retried, nor are 400, 402, 404 or client-side timeouts. The delay starts at 1 second and grows 1.5× per retry (capped at 30 seconds); a Retry-After header wins.

using var client = new BrowserSolverClient(new BrowserSolverClientOptions { MaxRetries = 5, RetryDelay = TimeSpan.FromMilliseconds(500) });
await client.WebsiteWebunlockerAsync(new WebsiteWebunlockerParams { Query = "https://example.com" }, new RequestOptions { MaxRetries = 0 }); // one request without retries

Batch requests

BatchAsync runs a function per item with at most 10 in flight (concurrency) and returns one BatchResult per item, in input order. A failing item never stops the others.

string[] inputs = { "https://example.com", "https://www.browsersolver.com" };
var results = await client.BatchAsync(inputs, (value, ct) =>
    client.WebsiteWebunlockerAsync(new WebsiteWebunlockerParams { Query = value }, cancellationToken: ct), concurrency: 5);
foreach (var result in results)
{
    if (result.Ok)
    {
        Console.WriteLine(result.Value!.Json);
    }
    else
    {
        Console.Error.WriteLine($"{inputs[result.Index]}: {result.Error!.Message}");
    }
}

Constant	Default	Description
BrowserSolverClient.DefaultConcurrency	10	Tasks run at the same time by batch
BrowserSolverClient.DefaultTimeout	TimeSpan.FromSeconds(120)	Request timeout
BrowserSolverClient.MaxRetries	3	Retry attempts after a network error, a 408/5xx or a rate limit
BrowserSolverClient.RetryBackoffFactor	1.5	Exponential backoff multiplier
BrowserSolverClient.DefaultRetryDelay	TimeSpan.FromSeconds(1)	Delay before the first retry

Configuration

using var client = new BrowserSolverClient(new BrowserSolverClientOptions
{
    ApiKey = Environment.GetEnvironmentVariable("BROWSERSOLVER_API_KEY"),
    Timeout = TimeSpan.FromSeconds(60), // default 120 s
    HttpClient = myHttpClient,           // optional, you keep ownership
});

Endpoints

9 methods, generated from the OpenAPI document.

Method	HTTP	Description
JobsAsync	GET /v1/jobs/{id}	Poll the status, progress (0–100) and result of a job started with is_async=true. Polling is free. Poll until status is terminal: Completed…
StatsAsync	GET /v1/stats	Infrastructure health for an engine or endpoint over the last hour. Not scoped to your account or tenant. Enabled per account: HTTP 403 mea…
UsageAsync	GET /v1/usage	Retrieve real-time usage statistics and credit balance for your BrowserSolver account.
WebsiteAntibotAsync	GET /v1/website/antibot	Single-pass scan that names the bot-protection vendor in front of a URL so you can choose the right BrowserSolver fetch tier next.
WebsiteCrawlerAsync	GET / POST /v1/website/crawler	Fast HTTP pull of public HTML with no browser session. Ideal when the first response already contains the content you need.
WebsiteRenderingAsync	GET /v1/website/rendering	Run a managed browser session against a public URL and collect the HTML after client-side scripts finish. Prefer Crawler for static markup;…
WebsiteScreenshotAsync	GET / POST /v1/website/screenshot	Turn any public URL into a PNG, JPEG, WebP, or PDF asset rendered by BrowserSolver. No local Chromium fleet to operate.
WebsiteTechnologyAsync	GET / POST /v1/website/technology	Map CMS, frameworks, analytics, CDN, and security tooling exposed by a public URL. Choose simple lists or expert metadata with confidence s…
WebsiteWebunlockerAsync	GET / POST /v1/website/webunlocker	BrowserSolver's highest HTML fetch tier for retail and marketplace hosts on your account whitelist. Solves persistent bot challenges that s…

All BrowserSolver SDKs

SDK	Package	Install
Node.js	@browsersolver/sdk	npm install @browsersolver/sdk
Python	browsersolver	pip install browsersolver
Go	browsersolver-go	go get github.com/browsersolver/browsersolver-go
.NET	BrowserSolver	dotnet add package BrowserSolver
Ruby	browsersolver	gem install browsersolver
PHP	browsersolver/sdk	composer require browsersolver/sdk
Java	browsersolver-java	build from source, see its README
CLI	@browsersolver/cli	npm install -g @browsersolver/cli
MCP server	@browsersolver/mcp	npx -y @browsersolver/mcp

License

MIT — see LICENSE.