TL;DR

  • SoftInBit Dev Tools is a free set of 50 developer tools. Everything you paste is processed in your browser and never sent to a server.
  • Next to the usual JSON, Base64, regex and diff tools, there are tools made for .NET work: a stack trace cleaner, a SQL Server execution plan viewer, a Serilog log viewer, and converters for appsettings.json, curl, JSON and connection strings.
  • No sign-up, no limits. Below is a short tour with screenshots and what each tool is good for.

Reading time: 7 min

It is a familiar moment. A production exception lands in the team channel, and someone pastes it into the first “stack trace formatter” a search engine returns. Ten minutes later, someone else pastes a JWT into an online decoder, and a connection string with a password into a “connection string validator”.

Every one of those sites received data that should never have left the company.

That is why we built SoftInBit Dev Tools: tools we use in our own .NET work, where the processing happens in your browser tab. Paste a token, a log file or an execution plan, and nothing is uploaded. Every tool page shows a Runs locally · nothing uploaded badge, and that is a design rule, not a slogan.

What “runs locally” means

  • Your input stays in the tab. Formatting, decoding, hashing, diffing and validation all run as JavaScript in your browser. There is no backend that receives your data.
  • Some tools load an open-source library (for example YAML, SQL formatting or QR codes) from a public CDN the first time you open them. That download is code coming to you; your input does not go anywhere.
  • Share links keep their state after the #. Tools that offer a share link put the state in the URL fragment, which browsers never send to the server. Still, don’t share a link that contains a secret.
  • The site counts page views, like any website. What you paste is not part of that.

Built for .NET work

These are the tools you won’t find on a generic “online JSON formatter” site.

.NET Stack Trace Cleaner

Paste a raw exception from a log, a test runner or a crash report. The tool:

  • splits it into the outer exception and every inner exception,
  • removes compiler noise from async methods and lambdas (<>c__DisplayClass, MoveNext, state machines),
  • collapses framework frames so only your code stands out,
  • and points at the likely origin: the first frame in your own code under the root cause.

.NET Stack Trace Cleaner showing a SqlException traced back to OrderRepository.cs line 58

In the example above, a 40-line wall of text becomes one line: the SqlException started in OrderRepository.AddAsync, at OrderRepository.cs:58. The result can be copied as Markdown for a ticket or a pull request.

at Clean up your own stack traceTurn a wall of exception text into the root cause and the line in your code that started it. Free, runs in your browser. Open tool →

SQL Server Execution Plan Viewer

Paste the XML of an estimated or actual execution plan (or open a .sqlplan file from SSMS). You get the operator tree and a list of findings ranked by how much they matter, each with an explanation:

  • implicit conversions that prevent an index seek,
  • key lookups that run thousands of times,
  • plans compiled for different parameter values (parameter sniffing),
  • row estimates that are wildly off, memory grants, spills and missing indexes.

SQL Server Execution Plan Viewer listing ranked findings such as an implicit conversion and a key lookup

Execution plans contain table names, column names and sometimes parameter values. That is exactly the kind of file you don’t want to upload to a third-party site.

PLAN Analyze an execution planSee the operator tree and the problems in a SQL Server plan, ranked by how much they matter. Free, runs in your browser. Open tool →

Serilog / CLEF Log Viewer

Got a log file from a server, but no Seq or Kibana nearby? Paste or drop Serilog’s compact JSON (CLEF) or JSON lines. You can filter by level, search messages and properties, filter by property value (OrderId = 42, Elapsed > 500), narrow down by time on the histogram, and open any entry to see all its properties and the exception.

Serilog CLEF Log Viewer with a level filter, a time histogram and a list of structured log entries

appsettings.json ⇄ Environment Variables

Moving an app to Docker or Kubernetes means turning nested configuration into Section__Key environment variables, and arrays into Section__0, Section__1. This tool does it in both directions and writes the output in the format you need: .env, Docker Compose, Kubernetes, Azure App Service settings, PowerShell, bash, launchSettings.json or dotnet user-secrets commands.

It also flags keys that look like secrets (connection strings, signing keys) and tells you to keep them out of source control.

appsettings.json to environment variables converter producing .env output and flagging two secret keys

curl to C# HttpClient

Copy a request from your browser’s network tab or an API’s documentation as curl, paste it, and get HttpClient code for modern .NET: plain, or as a typed client registered with AddHttpClient. Form bodies, JSON bodies, headers and authentication are converted, and the notes warn you when the request contains credentials that should come from configuration instead.

curl to C# HttpClient converter turning an OAuth token request into C# code

JSON to C# Classes

Paste a JSON response and get records or classes ready for System.Text.Json. You choose the root type name, namespace, property naming, collection type and number types. [JsonPropertyName] attributes are added only where the JSON name differs from the C# name, and dates and GUIDs are detected.

JSON to C# converter generating records with JsonPropertyName attributes

JWT Decoder & Verifier

Paste a token to see the header and payload, every claim explained, and the expiry in plain words (“valid, expires in 55 min”). You can verify the signature with a shared secret or a public key, and that check also happens locally. If you are issuing tokens yourself, Issuing and Validating JWT Access Tokens in ASP.NET Core shows the server side.

JWT Decoder showing the decoded header, payload and claims of a token that is valid for 55 more minutes

Connection String Builder & Parser

Paste any SQL Server, PostgreSQL, MySQL or similar connection string. Every key is shown with its meaning, and risky settings are flagged: TrustServerCertificate=True in production, a missing Application Name, a plain-text password. You can edit the fields and copy the result as a connection string, an appsettings.json snippet, environment variables or C#. The password is hidden on screen by default.

Connection String Builder flagging TrustServerCertificate=True as a warning

More in the same group:

The everyday tools

These are the tools almost every developer opens every week. Here they all work offline from your data, too.

Text Compare

Diff two texts with word-level highlights, side by side or inline. Ignore whitespace or case, collapse unchanged lines, jump between changes, and merge a change from one side to the other with one click.

Text Compare showing a side-by-side diff of two C# files with word-level highlights

Regex Tester

JavaScript regular expressions with live matching, named groups, a replace preview and a library of common patterns (email, URL, GUID, ISO date, IP address). A backtracking guard stops patterns that would freeze the tab.

Regex Tester matching ISO timestamps in a log with named groups

And the rest

Small things that save time

  • Press / on the tools page to search, and Ctrl+Enter (Cmd+Enter on a Mac) to run a tool’s main action.
  • Focus mode hides everything except the tool.
  • Most tools have an Example button, so you can see what they do before you paste your own data.
  • The tool interfaces are available in English, Turkish, German, Spanish and French, and they all work in dark mode.

What’s next

We add tools when our own projects need them. If there is a tool you keep searching for, especially one for .NET, SQL Server or Azure work, tell us and it may be the next one.

Start at softinbit.com/tools.

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How this article was made: drafted with AI assistance, then reviewed by Softinbit Technology before publishing.