I Built a Timestamp Converter That Doesn't Suck (And It's Free)

Source: Dev.to

Debugging API logs often means staring at a raw value like 1706745600 and wondering “What date is this even?”
A quick Google search for “unix timestamp converter” usually lands you on pages cluttered with ads, dropdowns for selecting “Unix timestamp (seconds)”, more ads, and a sign‑up prompt.

I got tired of that. Over a weekend I built TimeStampConverter.net – a timestamp converter that just works.

What Makes It Different?

Auto‑Detection

Paste anything. The tool figures out the format automatically:

No dropdowns, no extra clicks.

One Paste, Seven Formats

A single paste shows all formats at once:

Unix (seconds):     1706745600
Unix (ms):          1706745600000
ISO 8601 (UTC):     2024-01-31T17:00:00.000Z
ISO 8601 (Local):   2024-01-31T12:00:00.000-05:00
RFC 2822:           Wed, 31 Jan 2024 12:00:00 -0500
Human:              January 31, 2024 12:00:00 PM
Relative:           2 hours ago

Each line has a copy button for quick pasting.

400+ Timezones

A searchable timezone dropdown lets you jump to any zone (e.g., type “Tokyo”).

Date Math Built‑In

• Add/subtract years, months, days, hours, minutes, seconds
• Calculate duration between two timestamps
• Handles DST and leap years correctly

Bulk Conversion

Paste multiple timestamps (one per line) and convert them all at once – perfect for log analysis.

URL Sharing

Share a specific timestamp via a link, e.g. https://timestampconverter.net?ts=1706745600.

Dark Mode by Default

Because many of us debug at 2 AM.

Zero Tracking

No analytics, no ads, no signup, no cookies. Everything runs client‑side.

The Tech Stack

I kept it brutally simple:

{
  "dependencies": {
    "dayjs": "^1.11.10"
  }
}

• Vanilla JavaScript – No React, Vue, or build step
• day.js – Lightweight date library (~2 KB)
• Cloudflare Pages – Free hosting with global CDN

Total bundle size: ~50 KB

Why Vanilla JS?

• No state management needed
• No routing needed
• No virtual DOM needed
• Fast loading – a comparable React app would be >200 KB, while this loads in under 100 ms worldwide.

How Auto‑Detection Works

The core is a simple regex‑based detector:

function detectTimestampFormat(input) {
  const trimmed = input.trim();

  // Unix timestamp (10 digits = seconds)
  if (/^\d{10}$/.test(trimmed)) {
    return { type: 'unix-seconds', value: parseInt(trimmed) };
  }

  // Unix timestamp (13 digits = milliseconds)
  if (/^\d{13}$/.test(trimmed)) {
    return { type: 'unix-ms', value: parseInt(trimmed) };
  }

  // ISO 8601 (starts with YYYY‑MM‑DDT)
  if (/^\d{4}-\d{2}-\d{2}T/.test(trimmed)) {
    return { type: 'iso8601', value: trimmed };
  }

  // RFC 2822 (starts with day name)
  if (/^[A-Za-z]{3},\s\d{2}\s[A-Za-z]{3}\s\d{4}/.test(trimmed)) {
    return { type: 'rfc2822', value: trimmed };
  }

  // Generic date parsing with dayjs
  const parsed = dayjs(trimmed);
  if (parsed.isValid()) {
    return { type: 'generic', value: trimmed };
  }

  return { type: 'invalid', value: null };
}

Once detected, conversion is straightforward:

function convertTimestamp(detected) {
  let date;

  switch (detected.type) {
    case 'unix-seconds':
      date = dayjs.unix(detected.value);
      break;
    case 'unix-ms':
      date = dayjs(detected.value);
      break;
    default:
      date = dayjs(detected.value);
  }

  return {
    unixSeconds: date.unix(),
    unixMs: date.valueOf(),
    iso8601UTC: date.utc().format(),
    iso8601Local: date.format(),
    rfc2822: date.format('ddd, DD MMM YYYY HH:mm:ss ZZ'),
    humanReadable: date.format('MMMM D, YYYY h:mm:ss A'),
    relative: date.fromNow()
  };
}

Deployment on Cloudflare Pages

Deploying is a breeze:

# 1. Build (nothing to build for vanilla JS!)
# 2. Deploy
wrangler pages deploy . --project-name=timestamp

# Done. Live globally in ~30 seconds.

Cloudflare provides:

• Unlimited bandwidth on the free tier
• 300+ edge locations
• Automatic HTTPS
• Preview deployments for every git push
• Built‑in analytics

All for $0/month.

What I Learned

1. Sometimes Vanilla JS is the Right Choice – Small utilities can beat frameworks on performance.
2. Auto‑Detection is Magical UX – Users love tools that “just work.”
3. Dark Mode Should Be Default – Dev tools are often used at night.
4. Cloudflare Pages Is Underrated – Free, unlimited, and fast for global users.
5. Solve Your Own Problem – Building something you need validates its usefulness.

What’s Next?

Potential features:

• Browser extension (right‑click → convert)
• API endpoint for programmatic use
• Advanced date‑math (e.g., business‑day calculations)
• Export options (CSV, JSON) for bulk results

Feel free to open an issue or submit a PR if you’d like to help!

Automatic Access

• Cron expression validator
• ISO week number calculator

But honestly, the tool already does what I need, so I may leave it as‑is.

Try It Yourself

TimeStampConverter.net – No signup, no tracking, no BS. Just timestamps. Bookmark it if you find it useful.

FAQ

Q: Is this open source?
A: Not yet, but I’m considering it. If there’s interest, I’ll put it on GitHub.

Q: How do you make money from this?
A: I don’t. It costs $0/month to run. I might add a “buy me a coffee” button someday.

Q: Can I use this for my app/API?
A: Everything runs client‑side, so yes. If you need a server‑side API endpoint, let me know – I might build one.

Q: What about privacy?
A: All conversions happen in your browser. I cannot see what you convert. Cloudflare logs basic CDN metrics (requests per region, bandwidth) but no user data.

Q: Can you add features?
A: Maybe! Drop a comment below or email me through the site.