The question is not the price. It is what the filter removes.
Almost every filter on this page stops bacteria and protozoa — E. coli, salmonella, giardia, cryptosporidium. That covers a Quebec stream, a lake, a doubtful well.
Almost none of them stop viruses. Hollow fibre at 0.1 or 0.2 µm lets them through: a virus is 10 to a 100 times smaller. It matters where human sewage may have reached the water — downstream of a village, after a flood, or travelling abroad. 2 models here handle viruses, and they say so.
The straw — one person, in a bag
You drink straight from the source. Nothing to set up, nothing to wait for. The cheapest format, and it fits anywhere — but you drink bent over the water, and you cannot fill a bottle for later.
| Model | Rating | Bacteria | Protozoa | Viruses | Taste, metals | Capacity |
|---|---|---|---|---|---|---|
| LifeStraw Personal | 0,2 µm | yes | yes | no | no | 4 000 L |
| LifeStraw Peak Solo | 0,2 µm | yes | yes | no | no | 2 000 L |
| Sawyer Mini | 0,1 µm | yes | yes | no | no | 378 000 L |
| Sawyer Micro Squeeze | 0,1 µm | yes | yes | no | no | 378 000 L |
LifeStraw Personal
0,2 µm · 4 000 L · 46 g
The classic, and the cheapest here. 121,655 reviews: the best-selling filter in the world. Bacteria and parasites, not viruses.
LifeStraw Peak Solo
0,2 µm · 2 000 L
The newer version, shorter, with a threaded tip that screws onto a store water bottle. Adds microplastics to the list.
Sawyer Mini
0,1 µm · 378 000 L
The threshold drops to 0.1 µm and the rated life is in another league — 378,000 litres, more than you will ever drink. Comes with a pouch and a cleaning syringe. Flow slows if you don't backflush it.
Sawyer Micro Squeeze
0,1 µm · débit supérieur au Mini
Same filtration as the Mini, but water flows faster. That is the Mini's main complaint, answered here for a few dollars less.
The bottle — fill, drink, move on
The filter is built into the bottle. Fill at the stream and drink while walking. The handiest format day to day, and the only tier here with a true virus purifier.
| Model | Rating | Bacteria | Protozoa | Viruses | Taste, metals | Capacity |
|---|---|---|---|---|---|---|
| LifeStraw Go, 1 L | 0,2 µm | yes | yes | no | yes | 1 L à la fois |
| LifeStraw Go, stainless steel | 0,2 µm | yes | yes | no | yes | 1 L à la fois |
| Katadyn BeFree, 1 L | 0,1 µm | yes | yes | no | no | 1 L à la fois |
| GRAYL GeoPress, 710 ml | purificateur | yes | yes | yes | yes | 710 ml en 8 s |
LifeStraw Go, 1 L
membrane + charbon · sans BPA
2 stages: the membrane for bacteria and parasites, activated carbon for taste and chlorine. The carbon is what makes water pleasant, not merely safe.
LifeStraw Go, stainless steel
isolée · membrane + charbon
The same mechanism in a double-walled insulated body. Heavier, but it keeps water cold and survives a drop on rock.
Katadyn BeFree, 1 L
0,1 µm · gourde souple Hydrapak
The flask folds flat when empty. Best flow in this tier: squeeze and it pours. The filter cleans by swishing it in water, no tool needed.
GRAYL GeoPress, 710 ml
purificateur · virus inclus · 8 s
The only one on this page that removes viruses — rotavirus, norovirus, hepatitis A — on top of bacteria, protozoa, heavy metals and chemicals. Fill, press like a French press, done in 8 seconds. The filter for travel where water is doubtful, not merely wild.
Light gravity — for 2 or 3, backpacking
Hang a bag, let gravity work, and filtered water flows into your containers while you set up camp. No effort, and enough for several people.
| Model | Rating | Bacteria | Protozoa | Viruses | Taste, metals | Capacity |
|---|---|---|---|---|---|---|
| LifeStraw Peak gravity, 3 L | 0,2 µm | yes | yes | no | no | 3 L |
| Waterdrop gravity, 5.7 L | 0,1 µm | yes | yes | no | no | 5,7 L |
| WRELS gravity, 3 L | 0,1 µm | yes | yes | no | no | 3 L |
LifeStraw Peak gravity, 3 L
3 L · 0,2 µm · 2 000 L
Compact, well made, folds down to nothing. The 2-person weekend size.
Waterdrop gravity, 5.7 L
5,7 L · 0,1 µm
Nearly double the volume for a similar price, and a 0.1 µm threshold. The most sensible compromise here.
WRELS gravity, 3 L
3 L · 0,1 µm · fibre creuse
The cheapest here. Only 2 reviews at the time of writing: the spec sheet is fine, but nobody has worn one out yet. Your call whether the price is worth the unknown.
Group gravity — cabin, camp, family
Past 6 litres you are no longer filtering for yourself: you are filtering for the table. This is also the size you keep at the cabin for when the well goes doubtful.
| Model | Rating | Bacteria | Protozoa | Viruses | Taste, metals | Capacity |
|---|---|---|---|---|---|---|
| Membrane Solutions Pro, 6 L | 0,1 µm | yes | yes | no | yes | 6 L |
| MSR AutoFlow XL, 10 L | 0,2 µm | yes | yes | no | no | 10 L |
| LifeStraw Peak purifier, 8 L | purificateur | yes | yes | yes | yes | 8 L |
Membrane Solutions Pro, 6 L
6 L · 0,1 µm · 4 étages · NSF 42/372/401
4 stages, including carbon for chlorine and odour, and 3 NSF certifications. A lot of filtration for the money.
MSR AutoFlow XL, 10 L
10 L · marque d'expédition
10 litres, with MSR's reputation behind it. Guide and expedition gear — you pay for it, and it lasts.
LifeStraw Peak purifier, 8 L
8 L · purificateur · virus inclus
The only gravity system here that handles viruses. 8 litres hanging, and safe water even from a source touched by sewage. That peace of mind has a price, and it is high.
The countertop — everyday water at home
We are past backpacking now. These sit on the counter, filter tap water every day, and keep working during a boil water advisory or a power failure — none of them needs electricity.
| Model | Rating | Bacteria | Protozoa | Viruses | Taste, metals | Capacity |
|---|---|---|---|---|---|---|
| iSpring CT10-W | charbon | no | no | no | yes | au robinet |
| Purewell 3-stage, 0.01 µm | 0,01 µm | yes | yes | yes | yes | comptoir, inox |
| Travel Berkey, 4.8 L | éléments noirs | yes | yes | claimed | claimed | 4,8 L |
| Big Berkey, 8.5 L | éléments noirs | yes | yes | claimed | claimed | 8,5 L |
| Royal Berkey, 12.3 L | éléments noirs | yes | yes | claimed | claimed | 12,3 L |
iSpring CT10-W
se branche au robinet · multi-étages
Simplest and cheapest: it connects straight to the tap, no drilling, no plumbing. For taste and chlorine day to day. It depends on mains pressure — useless in a water outage.
Purewell 3-stage, 0.01 µm
inox 304 · 0,01 µm · NSF 42/372
A threshold 10 times finer than the hollow fibre of hiking filters, in a stainless body, by gravity. The sensible alternative to a Berkey, at under half the price, with 1,177 reviews behind it.
Travel Berkey, 4.8 L
4,8 L · 2 éléments Black Berkey
The smallest Berkey, for one or 2 people. The black elements are the brand's whole point: they handle far more than bacteria, and they clean with a brush rather than being replaced.
Big Berkey, 8.5 L
8,5 L · 2 éléments Black Berkey
The family size, and the brand's best seller. 8 and a half litres sitting on the counter is also a drinking water reserve when the taps fail.
Royal Berkey, 12.3 L
12,3 L · 2 éléments Black Berkey
The large size, for a household of 4 or more, or a cabin you fill up rarely. Same mechanism as the Big, more reserve.
What none of them does
No filter on this page removes dissolved salt: sea water stays undrinkable. None removes nitrates from farm runoff, and none removes radioactive contamination. A filter clogged with silt also stops working — let muddy water settle first, or pre-filter it through a cloth.
And a filter is not a water supply. It makes a source drinkable; it does not create one. Stored water comes first.