What Is Packet Loss? Causes, Symptoms, Testing, and How to Fix It

Packet loss happens when some of the data travelling across a network fails to reach its destination.

In simple terms: bits of your internet traffic go missing along the way.

That can lead to:

• Laggy gaming
• Buffering streams
• Frozen video calls
• Robotic audio
• Slow-loading websites

Even tiny amounts of packet loss can wreck real-time activities like gaming, Zoom calls, streaming, and cloud applications. And unfortunately, it doesn’t take much. A network can look “connected” while still performing terribly underneath the surface.

The good news? Most packet loss problems are fixable once you know what’s causing them.

In this guide, we’ll explain:

• What packet loss actually is
• What causes it
• The symptoms to look out for
• How to test for packet loss
• How to fix it 

Packet Loss Definition

Packet loss is the failure of data packets to successfully travel across a network and reach their destination. It commonly causes lag, buffering, poor call quality, unstable internet connections, and slow network performance.

How Packet Loss Works

Every time you browse a website, join a Teams call, stream Netflix, or fire up an online game, your device sends and receives tiny chunks of data called packets.

Think of packets like little digital parcels travelling across the internet.

Each one contains:

• The source address
• The destination address
• The data itself
• Instructions for rebuilding the information correctly

Routers, switches, servers, and internet providers all help move these packets from one place to another. When everything works as it should, the receiving device rebuilds the packets seamlessly and you never notice a thing.

But when packets get delayed, corrupted, or dropped entirely, things start getting messy.

That’s packet loss.

Depending on the severity, you might notice:

• Buffering streams
• Crackly audio
• Delayed gameplay
• Lag spikes
• Websites hanging mid-load
• Video calls freezing 

Real-time applications are especially sensitive because there’s usually no time to resend missing data before the experience breaks down.

What Causes Packet Loss?

Unfortunately, packet loss isn’t caused by one single thing. Networks are messy little ecosystems, and problems can happen almost anywhere between your device and the wider internet.

The most common causes include:

• Network congestion
• Weak Wi-Fi signals
• Faulty hardware
• Software issues
• ISP network problems

Let’s break them down.

Network Congestion

This is one of the biggest culprits of packet loss. Congestion happens when too much data is trying to move across a network at the same time.

Routers and switches can only handle so much traffic before they start struggling. Once capacity gets overwhelmed, packets may simply get dropped to keep the network functioning.

Common causes include:

• 4K streaming
• Large downloads
• Cloud backups
• Multiple connected devices
• Peak-time broadband traffic
• Bandwidth-heavy applications

At home, congestion usually shows up as:

• Spotify stuttering
• Teams calls freezing
• Games lagging
• Websites loading painfully slowly

Basically: too many things fighting for bandwidth at once.

Wi-Fi Interference

Wi-Fi is brilliant when it works. And a huge pain in the digital rear when it doesn’t. 

Wireless signals weaken over distance and struggle with obstacles like:

• Brick walls
• Concrete floors
• Metal surfaces
• Foil-backed insulation

They’re also vulnerable to interference from:

• Nearby Wi-Fi networks
• Microwaves
• Bluetooth devices
• Smart home gadgets
• Baby monitors

If your Wi-Fi signal becomes unstable, packets can get lost before they even reach your device.

That’s why packet loss often gets worse:

• Further away from the router
• In busy apartment buildings
• In rooms with thick walls
• During high network usage

Faulty Network Hardware

Sometimes the problem is physical. Ageing or damaged hardware can interrupt data transmission and create unstable connections across the entire network.

Common hardware-related causes include:

• Faulty routers
• Overheating modems
• Damaged Ethernet cables
• Failing switches
• Old wireless adaptors
• Faulty network cards

And annoyingly, one weak link can affect everything connected to the network. If your router’s getting on a bit, network instability becomes far more likely.

Software or Configuration Issues

Behind every stable network sits a surprisingly long list of settings behaving themselves. When one of them isn’t, things can unravel quickly.

Common software-related causes include:

• Outdated firmware
• Driver issues
• Firewall conflicts
• VPN problems
• Incorrect QoS settings
• MTU mismatches
• Poor traffic prioritisation

Even small configuration issues can lead to:

• Random lag spikes
• Dropped packets
• Connection instability
• Poor VoIP quality

Keeping software updated goes a long way towards preventing problems before they start.

ISP or Carrier Problems

Sometimes the issue isn’t inside your home or office at all. Packet loss can also happen within your internet provider’s infrastructure.

Common ISP-related causes include:

• Routing problems
• Infrastructure congestion
• Maintenance work
• Faulty upstream hardware
• Peering issues between providers

If packet loss suddenly appears at certain times every evening, there’s a good chance congestion higher up the chain is involved. Especially in densely populated areas.

Common Symptoms of Packet Loss

Packet loss rarely kills your connection completely. It just makes everything feel slow, glitchy, and very, verrrry irritating.

One minute everything works perfectly. The next:

• Calls freeze
• Audio crackles
• Streams buffer
• Games lag
• Websites stop responding

The biggest problems usually appear during real-time activities where data needs to arrive instantly.

Lag During Online Gaming

Gaming absolutely hates packet loss. You can have decent download speeds and still end up teleporting backwards across the map because packets are disappearing mid-game.

Common gaming symptoms include:

• Rubber-banding
• Delayed actions
• Ping spikes
• Character teleporting
• Server disconnects
• Input lag

No gamer wants lag deciding the outcome of a match.

Streaming Buffering

Ah yes. The spinning loading wheel of doom.

Streaming platforms rely on a constant flow of packets to keep video playing smoothly.

When packets go missing:

• Streams buffer
• Video quality drops
• Playback pauses
• Content refuses to load properly

And suddenly your “one more episode” plan becomes “one more refresh.”

Frozen or Robotic Video Calls

Packet loss and video conferencing are not friends. When packets disappear during calls, conversations become awkward fast.

You might notice:

• Frozen screens
• Delayed responses
• Robotic audio
• Voices cutting out
• Choppy video
• Random disconnections

If your Teams calls sound like they’re being transmitted from the bottom of the ocean, packet loss is a likely suspect.

Failed Uploads or Downloads

Large file transfers rely on consistent data delivery.

If packets keep disappearing, uploads and downloads may:

• Stall halfway through
• Fail completely
• Restart repeatedly
• Corrupt files

Cloud backups and sync services like OneDrive or Google Drive can also become unreliable.

Packet Loss vs Latency

Packet loss and latency often get lumped together, but they’re different problems.

• Latency is delay
• Packet loss is missing data

High latency means packets arrive slowly. Packet loss means some packets never arrive at all.

You can have:

• High latency without packet loss
• Packet loss without high latency
• Or both together (which is where things get painful)

Both can affect:

• Gaming
• Streaming
• VoIP calls
• Remote working
• Cloud applications

How Much Packet Loss Is Acceptable?

Ideally? None. A healthy network should maintain extremely low packet loss levels.

Real-time applications like gaming, live streaming, and VoIP may experience issues even below 1%. Packet loss is one of those issues where “a little” can still feel like a lot.

How to Test for Packet Loss

If your connection feels unstable, there are a few reliable ways to check whether packet loss is involved.

Run a Ping Test

A ping test is one of the quickest ways to detect packet loss.

It works by sending small packets to another server and checking whether they successfully return.

If some packets fail to complete the round trip, packet loss is happening somewhere along the route.

You can run ping tests using:

• Windows Command Prompt
• macOS Terminal
• Linux Terminal
• Online ping tools
• Network monitoring software

Results typically show:

• Packet loss percentage
• Latency
• Response time

Use Traceroute

Traceroute helps identify where packets begin failing.

Instead of simply checking whether packets arrive, traceroute maps the full journey data takes across the network.

Along the way, it measures every “hop” between routers and servers.

If packets start disappearing at a particular point, traceroute helps pinpoint exactly where things are going sideways.

It’s especially useful for diagnosing:

• Packet loss
• Routing problems
• ISP congestion
• High latency
• Network bottlenecks

Use Network Monitoring Tools

Businesses often use professional monitoring tools to continuously track network reliability and performance.

Popular options include:

• Wireshark
• PingPlotter
• SolarWinds
• PRTG Network Monitor
• Nagios

These tools help identify:

• Packet loss trends
• Congestion
• Latency spikes
• Failing hardware
• Bandwidth problems

How to Fix Packet Loss

There’s no universal “fix everything” button for packet loss. But most causes are completely manageable once you narrow the problem down.

Restart Your Router and Modem

Yes. Really. “Have you tried turning it off and on again?” became an IT cliché for a reason.

Restarting networking equipment can clear:

• Temporary congestion
• Memory issues
• Minor software glitches
• Connection instability

To properly power cycle:

1. Turn everything off
2. Wait 30 seconds
3. Restart the modem first
4. Restart the router second

Occasionally, your router’s just having a day.

Switch to Ethernet Instead of Wi-Fi

Wired Ethernet connections are usually faster, more stable, and far less vulnerable to interference.

If packet loss mainly happens during:

• Gaming
• Video calls
• Streaming
• Large uploads

…switching to Ethernet can make a huge difference. Especially in busy Wi-Fi environments.

Move Closer to the Router

Weak Wi-Fi signals often increase packet loss.

A few simple improvements can help:

• Reposition the router centrally
• Reduce physical obstructions
• Avoid placing routers behind furniture
• Use mesh Wi-Fi systems
• Change crowded wireless channels

Sometimes moving the router two feet can improve the entire network.

Reduce Network Congestion

Too many devices hammering the connection at once can overwhelm the network.

To reduce congestion:

• Pause large downloads
• Limit simultaneous streaming
• Schedule backups overnight
• Prioritise traffic with QoS settings
• Disconnect unused devices

Less traffic means fewer dropped packets. Simple.

Update Firmware and Drivers

Outdated software can create compatibility and stability problems.

Regularly update:

• Router firmware
• Network drivers
• Operating systems
• Wireless adaptors

Updates often include performance fixes, security improvements, and network stability patches.

Replace Faulty Hardware

Old hardware doesn’t age gracefully.

If packet loss persists, check:

• Ethernet cables
• Routers
• Switches
• Modems
• Wireless adaptors

Sometimes a flaky £5 cable is all it takes to wreck an otherwise perfectly healthy connection.

Contact Your ISP

If everything inside your network looks fine, the issue may sit with your provider.

Your ISP can investigate:

• Routing issues
• Infrastructure faults
• Congestion
• Upstream packet loss

Before contacting them, gather:

• Ping test results
• Traceroute outputs
• Times problems occur
• Examples of affected services

The more evidence you have, the faster things usually move.

Why Packet Loss Matters for Businesses

Packet loss affects productivity, customer experience, and operational reliability.

For businesses, it can lead to:

• Poor video conferencing
• Unstable cloud apps
• Failed file transfers
• VoIP problems
• Slow remote working
• Frustrated customers

And when teams rely heavily on cloud infrastructure, even small amounts of instability become noticeable very quickly.

Reliable connectivity is business-critical for many.

How to Prevent Packet Loss

You can’t prevent every network issue forever.

But proactive maintenance dramatically reduces the chances of recurring packet loss.

Best practices include:

• Monitoring network performance regularly
• Keeping firmware updated
• Using quality networking hardware
• Avoiding overloaded Wi-Fi networks
• Replacing ageing equipment
• Optimising router placement
• Using traffic prioritisation
• Designing scalable infrastructure

For businesses, managed network monitoring can also help detect problems before users even notice them.

Final Thoughts

Packet loss is one of those problems you rarely notice until suddenly everything starts buffering, freezing, crackling, or disconnecting at once.

The good news? Most packet loss issues are fixable once you know where to look.

Whether it’s overloaded Wi-Fi, ageing hardware, ISP congestion, or a rogue Ethernet cable on the verge of croaking, a few smart fixes can make your connection feel dramatically more stable.

Less lag. Fewer freezes. Far less shouting at the router. Lovely stuff.

Frequently Asked Questions

Is Packet Loss Bad?

Yes. Packet loss can seriously affect internet performance, especially during gaming, streaming, video calls, and cloud-based work. Even small amounts can cause lag, buffering, robotic audio, and unstable connections.

Can Packet Loss Be Fixed?

Usually, yes. The fix depends on the root cause, but common solutions include:

• Restarting your router
• Switching to Ethernet
• Improving Wi-Fi coverage
• Updating firmware
• Reducing congestion
• Replacing faulty hardware
• Contacting your ISP

Does Wi-Fi Cause Packet Loss?

Wi-Fi itself doesn’t directly cause packet loss, but weak signals and wireless interference commonly contribute to it.

Packet loss is more likely when:

• You’re far from the router
• Multiple devices share the network
• Nearby networks create interference
• Physical obstacles weaken the signal

What Is a Good Packet Loss Percentage?

Ideally, packet loss should remain at 0%. Most networks still perform well below 1%, but real-time applications like gaming and VoIP can experience problems even with very small amounts of packet loss.

Can VPNs Cause Packet Loss?

Sometimes. VPNs can increase latency or packet loss due to:

• Encryption overhead
• Poor routing
• Congested VPN servers
• Weak VPN protocols

A quality VPN provider usually helps minimise these issues.