Welcome to Flashlight Guide

Whether you're looking for an everyday carry (EDC) light, a powerful searchlight for outdoor adventures, or a reliable tactical flashlight, understanding the technology behind modern flashlights will help you make the right choice. This guide covers everything from basic specifications to advanced features, plus our top product recommendations.

Flashlight Basics

Key Specifications Explained

Modern flashlights come with a variety of specifications. Here's what they mean:

Lumens

Measures total light output. More lumens = more light. A typical phone flashlight produces about 40-50 lumens, while high-powered flashlights can exceed 3,000 lumens.

Candela

Measures beam intensity at the center. High candela means the light can "throw" farther, even with modest lumens. Important for searchlights and throwers.

Beam Distance

The distance at which the flashlight produces 0.25 lux (roughly equivalent to full moon light). Expressed in meters or feet.

Runtime

How long the flashlight operates on a single charge or set of batteries. Usually measured until output drops to 10% of initial brightness.

IP Rating

Ingress Protection rating for dust and water resistance. IPX4 handles splashes, IPX7 survives submersion to 1 meter, IPX8 goes deeper.

CRI (Color Rendering Index)

Measures how accurately colors appear under the light. Higher CRI (90+) shows colors more naturally. Important for photography or identifying objects.

LED Technology

Nearly all modern flashlights use LED (Light Emitting Diode) technology, which offers significant advantages over older incandescent bulbs:

Popular LED brands include Cree (XM-L2, XHP series), Luminus (SST-40, SST-20), and Samsung (LH351D). The specific LED affects output, tint, and color rendering.

Understanding Lumens

Lumens measure the total amount of visible light emitted by a source. While more lumens generally means a brighter flashlight, it's not the only factor that determines usefulness.

How Many Lumens Do You Need?

Lumens Best For Example Uses
1-20 Close-up tasks Reading in bed, finding keyhole, checking map
20-100 General indoor use Power outage, walking to car, basic tasks
100-300 Walking, basic outdoor Dog walking, camping around site, home defense
300-700 Most EDC needs Trail hiking, search tasks, professional use
700-1500 Outdoor activities Night hiking, hunting, tactical operations
1500-3000+ Search & rescue, specialty SAR, security patrol, cave exploration

Lumens vs. Candela vs. Throw

A flashlight with 1,000 lumens can look very different depending on how the light is focused:

Floody Beam

Spreads light over a wide area. Great for close-range tasks and walking. Lower candela, shorter throw, but illuminates more space nearby. Example: the Wurkkos TS21 with its triple LED design provides excellent flood.

Throwy Beam

Concentrates light into a tight beam. Higher candela, longer throw distance, but narrower coverage. Example: the ThruNite Catapult Mini throws nearly 600 meters with only 680 lumens.

Pro Tip

For most everyday use, 300-700 lumens with a balanced beam profile is ideal. You rarely need maximum brightness, and having multiple modes lets you adapt to different situations while preserving battery life.

Flashlight Battery Guide

The battery determines runtime, output capability, and form factor. Modern flashlights use a variety of battery types, each with trade-offs.

Common Battery Types

18650 Li-ion

18mm x 65mm

  • Most popular enthusiast battery
  • 3.7V nominal, rechargeable
  • 2600-3500mAh capacity typical
  • 500+ charge cycles
  • High discharge rates available

Best for: EDC lights, high-powered compact flashlights

21700 Li-ion

21mm x 70mm

  • Larger, higher capacity than 18650
  • 3.7V nominal, rechargeable
  • 4000-5000mAh capacity typical
  • Becoming more popular
  • Used in Tesla vehicles

Best for: High-output lights needing longer runtime

CR123A Lithium

17mm x 34mm

  • 3V primary (non-rechargeable)
  • Excellent shelf life (10+ years)
  • Works in extreme temperatures
  • Higher cost per use
  • Tactical/professional favorite

Best for: Backup lights, emergency kits, compact tactical lights

AA / AAA Alkaline/NiMH

Standard sizes

  • Universally available
  • 1.5V (alkaline) or 1.2V (NiMH)
  • NiMH rechargeable recommended
  • Lower output than Li-ion
  • Familiar and convenient

Best for: Backup lights, gifting, simplicity

Why 18650 is the Enthusiast's Choice

The 18650 has become the standard for flashlight enthusiasts because it offers the best balance of size, capacity, and performance. Here's why:

Recommended Battery Chargers

If you use 18650 or other lithium cells, a quality charger is essential. Here are our top picks:

Nitecore UMS4

4-slot intelligent charger with USB-C input. Supports Li-ion, NiMH, and NiCd batteries. Fast charging at up to 3A per slot.

Check Price on Amazon

Nitecore New i4

Budget-friendly 4-slot option. Reliable and widely trusted. Supports multiple battery chemistries with automatic detection.

Check Price on Amazon

Battery Safety

Always use reputable battery brands. Cheap no-name 18650s may have inflated capacity claims and can be dangerous. Stick to cells from Samsung, Sony/Murata, LG, or Panasonic. Store batteries in a case, never loose in pockets with keys or coins.

Beam Patterns Explained

How a flashlight shapes its beam dramatically affects its usefulness. Understanding beam patterns helps you choose the right light for your needs.

Anatomy of a Flashlight Beam

Hotspot

The brightest center portion of the beam. In throwy lights, this is intense and focused. In floody lights, it may be barely distinguishable from the spill.

Spill

The dimmer area surrounding the hotspot. Wide spill provides peripheral awareness. Some tactical users prefer minimal spill for covert use.

Corona

The transition zone between hotspot and spill. Smooth transitions look more pleasant; harsh transitions can be distracting.

Reflector Types

Smooth Reflector (SMO)

Creates a focused beam with maximum throw. Tight hotspot with defined edges. Preferred for searchlights and tactical throw lights.

Orange Peel (OP)

Textured surface diffuses the beam slightly. Smoother hotspot-to-spill transition. Reduces artifacts and rings. Most versatile option.

TIR Optic

Total Internal Reflection lens. Very smooth, artifact-free beam. Can be designed for flood or throw. Common in high-end EDC lights.

Choosing the Right Beam Pattern

Use Case Recommended Beam Why
Indoor / Close work Flood / TIR Wide coverage without blinding hotspot
Trail walking / Hiking Balanced / OP reflector Good path illumination with distance awareness
Search & Rescue Throw / SMO reflector Maximum distance to spot targets
Everyday Carry Balanced / TIR Versatile for varied situations
Camping Flood Illuminate campsite broadly

Types of Flashlights

EDC (Everyday Carry)

Compact lights designed for daily pocket carry. Usually single 18650 or AA battery. Balance of output, size, and features.

  • Size: 3-5 inches typically
  • Output: 300-2000 lumens
  • Features: Pocket clip, multiple modes, USB charging

Good choice: Fenix PD36R Pro (2800 lumens, dual switches)

Keychain

Ultra-compact lights that attach to keys or clip to pockets. Usually under 3 inches. Great as backup or for light tasks.

  • Size: 1-3 inches
  • Output: 50-500 lumens typical
  • Features: Keyring, small clip, simple UI

Good choice: ThruNite Archer Mini (405 lumens, USB-C rechargeable)

Tactical

Built for professional and defensive use. Often feature tail switches, strobe modes, weapon mount capability, and extreme durability.

  • Size: 4-6 inches
  • Output: 500-3000+ lumens
  • Features: Tail switch, strobe, aggressive bezel

Good choice: Streamlight ProTac 2.0 (2000 lumens, professional grade)

Thrower / Searchlight

Optimized for maximum beam distance. Large reflector or specialized optics concentrate light into a tight, far-reaching beam.

  • Beam distance: 500-1500+ meters
  • Output: Varies (candela matters more)
  • Features: Large head, dedicated throw

Good choice: ThruNite Catapult Mini (598m throw, compact)

Headlamp

Hands-free lighting worn on the head. Essential for camping, running, working, and any activity requiring both hands.

  • Output: 100-1500 lumens
  • Weight: Important factor
  • Features: Multiple modes, red light option

Lantern

360-degree area lighting. Some flashlights include lantern modes using diffusers. Dedicated lanterns excel at campsite illumination.

  • Output: 100-500 lumens typically
  • Coverage: 360 degrees
  • Features: Hang loop, stable base, long runtime

Our Top Flashlight Picks

Based on performance, value, and user feedback, here are our recommendations across different categories:

Best Value

Wurkkos TS21

3500 Lumens 217m Throw 21700 Battery

Incredible performance for the price. The TS21 runs Anduril 2.0 firmware, giving enthusiasts deep customization options. Triple SST20 LEDs provide a floody, pleasant beam. Available in multiple color temperatures (4000K warm, 5000K neutral, 6500K cool).

  • Anduril 2.0 UI for customization
  • High CRI option available
  • Magnetic tail cap
  • Outstanding price-to-performance
Check Price on Amazon
Best Compact

ThruNite Archer Mini

405 Lumens 87m Throw Built-in Battery

When you need a light that disappears in your pocket until needed, the Archer Mini delivers. At just 3.26 inches, it's truly compact yet produces useful output. USB-C charging and a simple tail switch make it foolproof.

  • Extremely pocketable
  • USB-C rechargeable
  • Simple, reliable operation
  • Great build quality for the size
Check Price on Amazon
Best Compact Thrower

ThruNite Catapult Mini

680 Lumens 598m Throw 18350 Battery

Need to light up distant objects without carrying a large searchlight? The Catapult Mini uses a small head diameter and specialized optic to achieve remarkable throw from a compact package. Ideal for spotting trail markers, wildlife, or search applications.

  • Incredible throw for the size
  • Compact and lightweight
  • USB-C rechargeable
  • Quality build
Check Price on Amazon
Best Professional

Streamlight ProTac 2.0

2000 Lumens 17300 Candela Proprietary Battery

Streamlight has decades of experience making lights for law enforcement and military. The ProTac 2.0 combines their reliability with modern output. Programmable modes let you configure the light for your specific needs.

  • Legendary Streamlight reliability
  • TEN-TAP programmable modes
  • USB rechargeable
  • Backed by lifetime warranty
Check Price on Amazon
Best Budget AA

ThruNite Archer 2A V3

500 Lumens 93m Throw 2x AA Battery

A fantastic entry point into quality flashlights. Runs on commonly available AA batteries (works with NiMH rechargeables too). The dual-switch interface provides quick access to all modes. Excellent for gifting or keeping in the car.

  • Uses common AA batteries
  • Solid construction
  • Intuitive dual-switch
  • Affordable quality
Check Price on Amazon

Flashlight Buying Guide

Questions to Ask Yourself

  1. What's the primary use?

    EDC, camping, tactical, professional, emergency backup? This determines size, output, and features you'll need.

  2. What size is acceptable?

    Pocket carry requires compact lights. Bag carry opens up larger, more powerful options.

  3. Rechargeable or replaceable batteries?

    USB rechargeable is convenient for daily use. Replaceable batteries offer backup options in the field.

  4. How much output do you actually need?

    Be realistic. 300-700 lumens handles most tasks. Ultra-high output drains batteries fast and generates heat.

  5. What's your budget?

    Quality budget options exist ($20-40). Mid-range ($50-100) offers excellent value. Premium ($100+) adds refinement.

Red Flags When Shopping

Trusted Flashlight Brands

These manufacturers consistently produce quality products with accurate specifications:

Fenix Streamlight Olight ThruNite Nitecore Wurkkos Sofirn Acebeam Zebralight Emisar

Frequently Asked Questions

How many lumens is "bright enough"?

For most people, 300-500 lumens is more than adequate for daily tasks. Your eyes adapt to available light, so even 100 lumens seems bright in darkness. Very high outputs (1500+ lumens) are useful outdoors but overkill for indoor use and drain batteries quickly.

Are cheap Amazon flashlights any good?

Some budget brands like Wurkkos and Sofirn offer excellent value. However, ultra-cheap no-name lights often have inflated specs, poor build quality, and potentially dangerous batteries. Stick to recognized budget brands for best results.

What's the difference between 18650 and 21700 batteries?

21700 cells are slightly larger (21mm vs 18mm diameter, 70mm vs 65mm length) and offer about 40% more capacity. Flashlights using 21700 are slightly larger but run longer. Both are excellent choices for rechargeable flashlights.

Why do flashlight enthusiasts care about "tint"?

LED tint describes the color temperature (warm to cool) and any color deviation (green/pink). Neutral white tints (4000-5000K) render colors more naturally than cool white (6500K+). High-CRI emitters show true colors, important for some users.

What is Anduril UI?

Anduril is open-source flashlight firmware created by enthusiast ToyKeeper. It offers extensive customization through click patterns. Many enthusiast-oriented lights (Wurkkos, Emisar, etc.) run Anduril. The learning curve is worth it for power users.

Do I need a tactical flashlight for self-defense?

A bright flashlight can disorient an attacker temporarily and help you identify threats. However, flashlights are tools, not weapons. Strobe modes are controversial; many find them more disorienting to the user. A reliable, bright light you know how to operate is what matters most.

How do I maintain my flashlight?

Keep threads clean and lightly lubricated with silicone grease. Clean contacts if you notice flickering. Store batteries at 40-60% charge for long-term storage. Avoid dropping on the lens. Check O-rings periodically for water-resistant models.