Fibre or ADSL: the real differences (speed, ping, stability)
Contents
Fibre is replacing copper telephone lines in country after country, and in many markets fibre subscriptions now outnumber DSL. Should you switch? Here are the concrete differences.
How each technology works
- ADSL: data travels as electrical signals over the copper pair of the phone line. The longer the line, the weaker the signal.
- Fibre (FTTH): data travels as light in a glass strand all the way to your home. Signal loss is tiny over urban network distances. Technical details: how FTTH fibre works.
Comparison
| Criterion | ADSL / VDSL | FTTH fibre |
|---|---|---|
| Typical download | 4 to 15 Mbps (ADSL), up to 50 Mbps (short VDSL) | 50 Mbps to 1 Gbps depending on plan |
| Typical upload | about 1 Mbps | high, depending on plan |
| Distance dependence | strong | almost none |
| Ping | 20 to 50 ms | 5 to 20 ms |
| Sensitivity to weather and interference | high (copper, humidity) | low |
| Evening speed | stable on the line side | stable if the network is not congested |
What changes day to day
- Several screens: on ADSL, two HD videos and a call are enough to saturate the line. On fibre you do not notice.
- Video calls and remote work: ADSL upload limits your image quality and file sending. See why upload matters.
- Games and downloads: a 50 GB game takes hours on ADSL and minutes on fibre.
- Stability: drop-outs caused by humidity or electrical interference are typical of copper.
Points to watch with fibre
- Connection: the building or street must be covered, then a technician installs the optical socket.
- Wi-Fi becomes the bottleneck: at 200 Mbps and above, an old router or a distant phone cannot keep up. Read fibre slow on Wi-Fi.
- Fibre is physically fragile: a bent or crushed optical cable causes signal loss (red LOS light). See red LOS light.
Measure your connection now. Start the test
What if fibre is not available?
A 4G/5G router can outperform ADSL where coverage is good, but speed varies with time and placement. Compare in 4G/5G router or fibre. Meanwhile, optimise your line with slow ADSL: improving your speed.
Our verdict
If fibre is available at your address and more than one person uses the connection, or you make video calls, work remotely or game, fibre is the right choice. ADSL remains acceptable for one person with light use.
Sources and further reading
Frequently asked questions
Is fibre more expensive than ADSL?
Prices change regularly and the gap is narrowing. Compare current offers: for the same speed, fibre is often better value.
Can I keep my landline number when switching to fibre?
It depends on the provider and the plan. Ask customer service before switching.
Does fibre work during a power cut?
No, the router and ONT need electricity. A small UPS keeps internet running during an outage.
The SpeedFibre team Guides written and reviewed by a telecom engineer specialised in fibre optics (FTTH), with more than 8 years of hands-on network maintenance and measurement. Editorial policy.
Related guides
- Understanding your connectionHow FTTH fibre works: from the exchange to your router
OLT, splitter, distribution point, wall socket, ONT: the path of the fibre signal to your home, explained by an FTTH technician, and what it means for your speed.
- Mobile, 5G and satellite4G/5G router or fibre: which to choose for your home?
4G router, 5G router or fibre optic: comparing speed, stability, ping and installation, and when a mobile router is a good solution.
- TroubleshootingSlow ADSL: 9 tips to improve your speed
Is your ADSL slow? Filter, socket, extension, sync rate, interference: the checks that really gain speed, and when to switch to fibre.
- Understanding your connectionHow to read a speed test: download, upload, ping and jitter
Download, upload, ping, jitter: learn what each value of a speed test means, what a good result looks like and how to find the cause of a slow connection.
