DevStack

Category guide

Development

Format JSON and SQL, encode Base64, build QR codes, generate an HMAC secret, decode a JWT, capture a public page, and extract tags from one public HTML page.

Made for: Engineers formatting payloads, sharing links as QR codes, or creating a signing secret.

Tools in this category

QR Generator

Custom code creation for links, text, and contact cards.

JSON Formatter

Validation and cleanup for API payloads.

Base64 Encoder

Encode and decode strings or files in Base64.

SQL Formatter

Pretty-print queries with consistent keyword casing.

Website to Screenshot

Open a public URL and save the page's layout as a PNG or JPEG.

HTML Tag Extractor

Read one public page and list a chosen tag, such as links or image addresses.

Open Graph & Meta Tags

Read a public page and check the title, image, and tags used in social link previews.

JWT Secret Generator

Generate a random HMAC secret for HS256, HS384, and HS512.

JWT Decoder

Read a JSON Web Token header and payload, and check the signature with your own key.

Typical workflow

  1. 01

    Paste or upload

    Drop in the JSON, SQL, text, or file. QR Generator, JWT Secret, Website to Screenshot, and HTML Tag Extractor start from a URL or options instead of a file.

  2. 02

    Choose the action

    Format, compact, encode, decode, or generate. Set dialect, charset, indent, or key length before you run it.

  3. 03

    Read the preview

    Check validation errors, the tree view, or the generated secret before you copy it.

  4. 04

    Copy or export

    Copy the output, download a file, or take the QR as PNG or SVG.

Best practices

  • Repair JSON only after you have seen the error. Repair rewrites comments, trailing commas, and unquoted keys.
  • Pick the SQL dialect that matches the database. Auto-detect is a starting point, not a guarantee.
  • Use 256 bits or more for an HMAC JWT secret, and store the value in an environment variable.
  • A JWT decoder shows the payload even when the signature is unchecked. Treat that as readable data, not proof of who sent it.
  • HTML Tag Extractor reads one public page. It does not open the links it finds.
  • Raise QR error correction when you place a logo in the center.

Privacy & limits

Formatters and encoders send the payload to the DevStack API. Do not paste production secrets, customer data, or private keys into a formatter.

Frequently asked questions

Is the JWT tool a token debugger?

No. It generates a random HMAC secret for HS256, HS384, and HS512. It does not sign or decode a token.

Can Base64 encode a file?

Yes, up to 5MB. Decode can return text or a downloadable file.

Ready to try Development tools?

Open the category to launch any tool.

Open Development