Developer tool examples

All samples are illustrative. Processing stays in your browser where each tool says so. Jump to JSON diff pairs or browse by category below.

Status & home

Website status checker/
Paste a hostname or URL to see if the site responds (HEAD + GET).
Try this URL
```
https://example.com
```

Time

World time/time
Compare clocks across zones; search cities in the tool.
Sample zones to search
```
America/New_York
Europe/London
Asia/Tokyo
```
Epoch converter/epoch
Convert Unix seconds ↔ human dates (handy with JWT exp/iat).
Unix seconds
```
1704067200
```

Text & data

JSON editor/json
Format, validate, minify, tree view, repair suggestions.
Sample document
```
{
  "service": "api",
  "version": "1.0",
  "ok": true
}
```
YAML converter/yaml
YAML ↔ JSON in the browser.
YAML → paste in tool
```
service: api
version: "1.0"
ports:
  - 8080
  - 8443
```

Markdown preview/markdown

Live Markdown → HTML preview.

Sample Markdown

# Release notes
- Fixed **login** flow
- See `CHANGELOG.md` for details

XML tools/xml

Format, minify, validate, XML ↔ JSON.

Sample XML

<?xml version="1.0" encoding="UTF-8"?>
<config>
  <env name="staging" debug="true"/>
</config>

CSV editor/csv
Edit CSV; convert rows ↔ JSON arrays.
Sample CSV
```
name,role,active
Alice,admin,true
Bob,viewer,false
```

HTML editor & preview/html

Edit HTML with a live preview pane.

Sample HTML

<article>
  <h1>Hello</h1>
  <p>WebStatus.in <strong>examples</strong>.</p>
</article>

Text diff/diff
Line, word, or char diff; optional third input; JSON repair review.
Tip
```
Use the JSON pairs in the section below, or any two text blobs.
```

Word counter/word-count

Words, characters, reading time, top tokens.

Sample paragraph

API design is the contract between your server and every client. Small wording changes in error messages still deserve a diff.

Case converter/case
camelCase, snake_case, kebab-case, Title Case, and more.
Try converting these
```
user_profile_v2
apiResponseTimeMs
```
Base64/base64
Encode/decode text and small files (URL-safe option where supported).
Plain text to encode
```
Hello, API!
```

Web & API

Speed checker/speed
DNS, TCP, TLS, TTFB, and transfer timing for any URL.
Test URL
```
https://example.com
```
cURL builder/curl
Build commands with method, headers, JSON body, auth, then copy.
Conceptual request (fill in the builder)
```
POST https://api.example.com/v1/items
Content-Type: application/json

{"name":"demo","qty":1}
```
Campaign URL builder/campaign-url
UTM parameters for analytics-friendly links.
Example result
```
https://example.com/signup?utm_source=newsletter&utm_medium=email&utm_campaign=spring
```
URL encoder / decoder/url-encode
encodeURIComponent vs encodeURI; good for query strings.
String to encode
```
/search?q=hello world&sort=date
```

Encode & generate

Hash generator/hash
MD5 + SHA-1/256/512 from text or files (checksums, not secrets).
Text to hash
```
consistent-cache-key-v3
```

JWT debugger/jwt

Decode header/payload; verify HS* signatures in-browser.

Sample JWT (jwt.io style)

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

Color converter/color
Hex, RGB, HSL, native picker.
Try these inputs
```
#3b82f6
rgb(59, 130, 246)
hsl(217 91% 60%)
```
QR code generator/qr
Static QR from text or URL.
Encode this
```
https://webstatus.in/json
```

UUID generator/uuid

v4 and v7; batch copy; hyphen toggle.

Typical use

Use the tool to mint IDs for fixtures: order-550e8400-e29b-41d4-a716-446655440000

Password generator/password-gen
Length, charset toggles, entropy meter — uses crypto.getRandomValues.
Suggestion
```
Generate 20+ chars with letters, digits, and symbols for new service accounts.
```
Coupon generator/coupons
Human-readable promo codes with prefixes and patterns.
Pattern idea
```
Prefix SAVE + 8 alphanumeric segments
```

AI & LLM

Token calculator/tokens
Estimate tokens for prompts (model tokenizer in a worker).
Sample prompt prefix
```
Summarize the following API error log for an on-call engineer:
```
LLM RAM calculator/llm-ram
Rough VRAM needs for context + model weights.
Scenario
```
7B model, 8k context, batch 1 — use sliders in the tool.
```
Token speed simulator/token-speed
Tokens/sec → time to complete a generation.
Mental math check
```
500 tokens at 50 tok/s ≈ 10 s — adjust in UI.
```

Docs & SEO landings

JSON diff pairs

Paste Before into Original and After into Modified on /diff. Valid JSON also surfaces structure hints and breaking-change summary.

Price field type change (breaking)

String → number often breaks strict clients. Use Text Diff + JSON structure hints on /diff.

Before

{
  "id": "sku-1",
  "price": "19.99",
  "currency": "USD"
}

After

{
  "id": "sku-1",
  "price": 19.99,
  "currency": "USD"
}

Removed optional field

Removing keys can be safe or breaking depending on your API contract.

Before

{
  "user": "alice",
  "role": "admin",
  "legacyFlag": true
}

After

{
  "user": "alice",
  "role": "admin"
}

Sharing & embedding

Shared tool URLs are normal pages with a hash or ?s= short id. You can link or iframe the URL users copy from Share — there is no separate oEmbed endpoint yet. For production embeds, prefer linking out so CSP and cookie policies stay simple.

Text & data

JSON editor/json

Format, validate, minify, tree view, repair suggestions.

Sample document

{
  "service": "api",
  "version": "1.0",
  "ok": true
}

YAML converter/yaml

YAML ↔ JSON in the browser.

YAML → paste in tool

service: api
version: "1.0"
ports:
  - 8080
  - 8443

Markdown preview/markdown

Live Markdown → HTML preview.

Sample Markdown

# Release notes
- Fixed **login** flow
- See `CHANGELOG.md` for details

XML tools/xml

Format, minify, validate, XML ↔ JSON.

Sample XML

<?xml version="1.0" encoding="UTF-8"?>
<config>
  <env name="staging" debug="true"/>
</config>

CSV editor/csv

Edit CSV; convert rows ↔ JSON arrays.

Sample CSV

name,role,active
Alice,admin,true
Bob,viewer,false

HTML editor & preview/html

Edit HTML with a live preview pane.

Sample HTML

<article>
  <h1>Hello</h1>
  <p>WebStatus.in <strong>examples</strong>.</p>
</article>

Text diff/diff

Line, word, or char diff; optional third input; JSON repair review.

Tip

Use the JSON pairs in the section below, or any two text blobs.

Word counter/word-count

Words, characters, reading time, top tokens.

Sample paragraph

API design is the contract between your server and every client. Small wording changes in error messages still deserve a diff.

Case converter/case

camelCase, snake_case, kebab-case, Title Case, and more.

Try converting these

user_profile_v2
apiResponseTimeMs

Base64/base64

Encode/decode text and small files (URL-safe option where supported).

Plain text to encode

Hello, API!

Web & API

Speed checker/speed

DNS, TCP, TLS, TTFB, and transfer timing for any URL.

Test URL

https://example.com

cURL builder/curl

Build commands with method, headers, JSON body, auth, then copy.

Conceptual request (fill in the builder)

POST https://api.example.com/v1/items
Content-Type: application/json

{"name":"demo","qty":1}

Campaign URL builder/campaign-url

UTM parameters for analytics-friendly links.

Example result

https://example.com/signup?utm_source=newsletter&utm_medium=email&utm_campaign=spring

URL encoder / decoder/url-encode

encodeURIComponent vs encodeURI; good for query strings.

String to encode

/search?q=hello world&sort=date

Encode & generate

Hash generator/hash

MD5 + SHA-1/256/512 from text or files (checksums, not secrets).

Text to hash

consistent-cache-key-v3

JWT debugger/jwt

Decode header/payload; verify HS* signatures in-browser.

Sample JWT (jwt.io style)

eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

Color converter/color

Hex, RGB, HSL, native picker.

Try these inputs

#3b82f6
rgb(59, 130, 246)
hsl(217 91% 60%)

QR code generator/qr

Static QR from text or URL.

Encode this

https://webstatus.in/json

UUID generator/uuid

v4 and v7; batch copy; hyphen toggle.

Typical use

Use the tool to mint IDs for fixtures: order-550e8400-e29b-41d4-a716-446655440000

Password generator/password-gen

Length, charset toggles, entropy meter — uses crypto.getRandomValues.

Suggestion

Generate 20+ chars with letters, digits, and symbols for new service accounts.

Coupon generator/coupons

Human-readable promo codes with prefixes and patterns.

Pattern idea

Prefix SAVE + 8 alphanumeric segments

AI & LLM

Token calculator/tokens

Estimate tokens for prompts (model tokenizer in a worker).

Sample prompt prefix

Summarize the following API error log for an on-call engineer:

LLM RAM calculator/llm-ram

Rough VRAM needs for context + model weights.

Scenario

7B model, 8k context, batch 1 — use sliders in the tool.

Token speed simulator/token-speed

Tokens/sec → time to complete a generation.

Mental math check

500 tokens at 50 tok/s ≈ 10 s — adjust in UI.

JSON diff pairs

Paste Before into Original and After into Modified on /diff. Valid JSON also surfaces structure hints and breaking-change summary.

Price field type change (breaking)

String → number often breaks strict clients. Use Text Diff + JSON structure hints on /diff.

Before

{
  "id": "sku-1",
  "price": "19.99",
  "currency": "USD"
}

After

{
  "id": "sku-1",
  "price": 19.99,
  "currency": "USD"
}

Removed optional field

Removing keys can be safe or breaking depending on your API contract.

Before

{
  "user": "alice",
  "role": "admin",
  "legacyFlag": true
}

After

{
  "user": "alice",
  "role": "admin"
}

Examples for every tool

Status & home

Time

Text & data

Web & API

Encode & generate

AI & LLM

Docs & SEO landings

JSON diff pairs

Price field type change (breaking)

Removed optional field

Sharing & embedding

Examples for every tool

Status & home

Time

Text & data

Web & API

Encode & generate

AI & LLM

Docs & SEO landings

JSON diff pairs

Price field type change (breaking)

Removed optional field

Sharing & embedding