Ultimate List of Timestamp Tools for Developers

Comprehensive comparison of timestamp conversion tools, epoch converters, and datetime libraries. Find the right tool for your Unix time conversion, ISO 8601 formatting, and timezone handling needs.

Quick Comparison Table

At-a-glance comparison of popular timestamp tools across key features. All tools listed are actively maintained unless otherwise noted.

Tool	Timezone Support	Output Formats	Batch Processing	Privacy	Cost
Timestamp Generator	Full IANA	Unix (s/ms), ISO 8601, Human	No	Client-side only	Free
EpochConverter.com	Basic	Unix, ISO, RFC 2822	Yes	Server-side	Free (ads)
Luxon	Full IANA	Customizable	Programmatic	Client-side	Free (OSS)
Day.js	Plugin	Customizable	Programmatic	Client-side	Free (OSS)
World Time API	Full IANA	JSON	Via API	Server-side	Free
TimeAPI.io	Full IANA	JSON	Via API	Server-side	Free tier + Paid

Web-Based Timestamp Tools

Browser-based tools for quick conversions without installation. Best for one-off conversions, debugging, and learning timestamp concepts.

Timestamp Generator ★★★★★

Best for: Engineers who need accurate timezone-aware conversions with comprehensive output formats

Pricing: Free

Key Features

Unix seconds and milliseconds
ISO 8601 (UTC and zoned)
Full IANA timezone support
Luxon-powered conversions
Client-side only (no data storage)
Duration calculator
Date math calculator
Keyboard shortcuts

Pros

Comprehensive timezone database
Multiple output formats
Privacy-focused (client-side)
Additional calculator tools
Educational content library

Cons

No API access
No batch processing
Requires internet connection

Limitations: Web-only (no API or CLI)

EpochConverter.com ★★★★☆

Best for: Quick conversions and code snippets

Pricing: Free (ad-supported)

Key Features

Unix timestamp conversion
Batch conversion
Programming language snippets
RFC 2822 formatting
Countdown to dates

Pros

Quick and simple interface
Code examples in multiple languages
Batch conversion support
No registration required

Cons

Limited timezone support
Ad-heavy interface
Dated UI design
Limited output formats

Limitations: Basic timezone support, ads can be distracting

Unix-Timestamp.com ★★★☆☆

Best for: Minimal, quick conversions

Pricing: Free

Key Features

Current timestamp display
Timestamp to date conversion
Date to timestamp conversion
Countdown timers

Pros

Simple and fast
Clean interface
No ads
Mobile-friendly

Cons

Limited features
Basic timezone support
No advanced formatting options
No batch processing

Limitations: Very basic functionality, limited timezone options

CurrentMillis.com ★★★☆☆

Best for: JavaScript developers needing millisecond timestamps

Pricing: Free

Key Features

Current timestamp in milliseconds
Convert timestamp to date
Code snippets for various languages
Human-readable format conversion

Pros

Focuses on millisecond precision
Language-specific examples
Fast loading
Simple interface

Cons

Limited features
Basic timezone options
No batch conversion
Minimal documentation

Limitations: Limited customization, basic timezone handling

Libraries and APIs

Programming libraries for embedding timestamp functionality in your applications. These require coding but offer maximum flexibility and control.

DateTimeFormatter (Java) ★★★★★

Best for: Java applications requiring robust date-time handling

Pricing: Free (part of Java)

Key Features

Pattern-based formatting
Locale support
Timezone awareness
Parsing and formatting
Predefined formats (ISO_INSTANT, RFC_1123, etc.)

Pros

Industry standard for Java
Comprehensive formatting options
Thread-safe
Part of standard library

Cons

Java-specific
Learning curve
Verbose API
Not a standalone tool

Limitations: Java-only, requires coding

Moment.js ★★★☆☆

Best for: Legacy JavaScript projects

Pricing: Free (open source)

Key Features

Parse, validate, manipulate dates
Timezone support (with moment-timezone)
Duration calculations
Relative time
Multiple locales

Pros

Mature ecosystem
Extensive documentation
Large community
Rich feature set

Cons

In maintenance mode (use Luxon/Day.js instead)
Large bundle size
Mutable API (error-prone)
Performance issues

Limitations: Deprecated (maintenance mode), mutable API

Luxon ★★★★★

Best for: Modern JavaScript projects requiring timezone accuracy

Pricing: Free (open source)

Key Features

Immutable date objects
IANA timezone support
Duration and interval arithmetic
Locale-aware formatting
Modern JavaScript API

Pros

Modern immutable API
Excellent timezone support
Smaller than Moment.js
Active development
TypeScript support

Cons

Smaller ecosystem than Moment
Requires learning new API
Bundle size larger than native Date
Not as minimal as Day.js

Limitations: Requires JavaScript runtime

Day.js ★★★★☆

Best for: JavaScript projects prioritizing bundle size

Pricing: Free (open source)

Key Features

Moment.js-compatible API
Small bundle size (2KB)
Plugin architecture
Timezone support (via plugin)
Immutable

Pros

Extremely lightweight
Moment.js compatible API
Plugin system
Good performance

Cons

Requires plugins for advanced features
Smaller community than Luxon
Less comprehensive than Luxon
Timezone plugin adds size

Limitations: Limited built-in features (requires plugins)

date-fns ★★★★☆

Best for: Projects using functional programming patterns

Pricing: Free (open source)

Key Features

Functional programming approach
Tree-shakeable
Over 200 date functions
Timezone support (via date-fns-tz)
TypeScript support

Pros

Modular and tree-shakeable
Functional API
Rich function library
Active development

Cons

Timezone support requires separate package
Can be verbose
Learning curve
Different API than competitors

Limitations: Timezone support requires additional package

Python datetime ★★★★☆

Best for: Python applications and scripts

Pricing: Free (part of Python)

Key Features

Native Python date/time handling
Timezone support
Date arithmetic
Formatting and parsing
ISO 8601 support

Pros

Built into Python
No external dependencies
Well documented
Widely used

Cons

Limited timezone database
Requires pytz for comprehensive support
API inconsistencies
Not as intuitive as some alternatives

Limitations: Python-only, limited timezone database without pytz

Temporal (JavaScript) ★★★★☆

Best for: Future JavaScript projects

Pricing: Free (future JavaScript standard)

Key Features

Modern date/time API
Immutable
Timezone-aware
Calendar system support
Precise duration handling

Pros

Future JavaScript standard
Modern immutable API
Comprehensive feature set
Addresses Date object issues

Cons

Not yet standard
Requires polyfill
Large polyfill size
Still changing (Stage 3)

Limitations: Stage 3 proposal (not yet standard), requires polyfill

API Services

Cloud-based APIs for time synchronization and conversion. Ideal for server-side applications requiring accurate time from external sources.

World Time API ★★★★☆

Best for: Applications needing server time synchronization

Pricing: Free (no rate limits listed)

Key Features

Current time by timezone
Current time by IP
Timezone list
JSON response format
Free tier available

Pros

Simple REST API
No authentication required
Good documentation
Multiple timezone formats

Cons

External dependency
Network latency
No SLA on free tier
Limited features beyond current time

Limitations: Requires internet connection, external dependency

TimeAPI.io ★★★★☆

Best for: Production applications requiring time API

Pricing: Free tier: 100 requests/day, Paid: from $9/month

Key Features

Current time by timezone
Time conversion
Time calculations
Business days calculations
API for developers

Pros

Comprehensive API
Business day calculations
Good documentation
Reliable SLA on paid tiers

Cons

Costs money for production use
Rate limits
External dependency
Requires API key management

Limitations: Rate limits on free tier, costs for high volume

Command-Line Tools

Terminal-based utilities for shell scripts and automation. Essential for DevOps workflows and batch processing.

date (Unix CLI) ★★★★☆

Best for: Shell scripts and automation

Pricing: Free (part of Unix/Linux)

Key Features

Display/set system date
Format timestamps
Convert between formats
Timezone conversion
Calculate dates

Pros

Available everywhere
Powerful formatting
Shell integration
No dependencies

Cons

Complex syntax
Platform differences (GNU vs BSD)
Not beginner-friendly
Limited interactive features

Limitations: Command-line only, syntax can be cryptic

strftime.org ★★★★☆

Best for: Learning strftime format codes

Pricing: Free

Key Features

strftime format reference
Interactive format tester
Language-specific examples
Quick reference table

Pros

Excellent reference
Interactive testing
Multiple languages
Clean design

Cons

Not a conversion tool
Limited to strftime format
No timezone handling
No actual date conversion

Limitations: Reference only, not a conversion tool

Use Case Recommendations

Not sure which tool to choose? Here are recommendations based on common use cases.

Quick one-off conversions

Recommended: Timestamp Generator or EpochConverter.com

Why: Web-based tools are fastest for occasional use without installation

Production JavaScript application

Recommended: Luxon or date-fns

Why: Modern, well-maintained libraries with excellent timezone support

Bundle size critical project

Recommended: Day.js or native Date

Why: Day.js is only 2KB, native Date has zero overhead

Server-side time synchronization

Recommended: World Time API or TimeAPI.io

Why: Reliable external time sources prevent drift

Shell scripts and automation

Recommended: date (Unix CLI)

Why: Built-in tool with powerful formatting options

Java enterprise application

Recommended: java.time (DateTimeFormatter)

Why: Standard library, thread-safe, comprehensive

Python data pipelines

Recommended: datetime + pytz or Arrow

Why: Native integration with Python ecosystem

Learning timestamp concepts

Recommended: Timestamp Generator + educational content

Why: Comprehensive guides and interactive tool for hands-on learning

How to Choose the Right Tool

Consider Your Requirements

Frequency of Use
- Occasional: Web-based tools (Timestamp Generator, EpochConverter)
- Daily: CLI tools or libraries
- Programmatic: Libraries and APIs
Timezone Requirements
- Basic UTC conversion: Any tool works
- Multiple timezones: Timestamp Generator, Luxon, date-fns
- Historical accuracy: Luxon, java.time
Privacy Concerns
- Sensitive data: Client-side only tools (Timestamp Generator, libraries)
- No concerns: API services acceptable
Performance
- Bundle size critical: Day.js, native Date
- Speed critical: Native libraries (java.time, datetime)
- Accuracy critical: Luxon, NTP-synced APIs
Integration
- Existing codebase: Match language/framework
- New project: Modern libraries (Luxon, date-fns)
- Standalone tool: Web tools or CLI

Decision Tree

┌─ Need a library/API?
│  ├─ Yes
│  │  ├─ JavaScript?
│  │  │  ├─ Bundle size critical? → Day.js
│  │  │  ├─ Best timezone support? → Luxon
│  │  │  └─ Functional style? → date-fns
│  │  ├─ Java? → java.time (DateTimeFormatter)
│  │  ├─ Python? → datetime + pytz
│  │  └─ Other? → Check language-specific libraries page
│  └─ No (one-off conversion)
│     ├─ Need privacy? → Timestamp Generator (client-side)
│     ├─ Need batch? → EpochConverter.com
│     └─ In terminal? → date (Unix CLI)

Additional Resources

Timezone API Comparison - Compare major timezone and timestamp APIs
Best Date-Time Libraries by Language - Organized library recommendations for every major programming language
Complete Guide to Unix Timestamps - Deep dive into Unix time fundamentals
Timezone Conversion Best Practices - Avoid common timezone mistakes
JavaScript Date-Time Guide - Working with dates in JavaScript
Try Timestamp Generator - Free, privacy-focused timestamp conversion tool

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