Ink
The best fountain pen ink cartridges
Buying the wrong cartridges is the most common ordering mistake in this hobby. Here is which one fits what.
How this page is funded. Buying through a link here earns us a commission at no extra cost to you. It does not change what we recommend or the order we recommend it in, and we have not hands-on tested these products — see how we choose and the full disclosure.
There is no universal fountain pen cartridge. There is a widely used one — the international standard — and there are three major makers who use their own instead. Ordering the wrong kind is genuinely the most common mistake new owners make, and there is no adapter that fixes it.
| Brand | Cartridge | Notes |
|---|---|---|
| Pilot | Pilot proprietary (IC-100 and equivalents) | Nothing else fits. Converter is the CON-40 or CON-70. |
| LAMY | LAMY T10, proprietary | Nothing else fits. Converter is the Z28. |
| Platinum | Platinum proprietary | Includes the pigment Carbon Black cartridge. |
| Kaweco | International standard, short | The Sport barrel only takes the short version. |
| Jinhao | International standard | Most models also ship with a converter. |
| Faber-Castell | International standard | |
| Monteverde, Diamine, J. Herbin | International standard | Third-party colors for any standard pen. |
Quick picks
Ranked for the beginner buying their first setup. Every pick names who it is wrong for.
| # | Product | Best for | Price |
|---|---|---|---|
| 1 | No image Monteverde international standard cartridges The universal cartridge size, twelve to a pack, in the colors the original makers do not offer. | Any pen that takes the standard cartridge | Check price on Amazon #ad No live price right now. How this is funded |
| 2 | No image LAMY T10 cartridges, black The proprietary cartridge every LAMY fountain pen takes, and the only cartridge they take. | Refilling a Safari, AL-star or Vista | Check price on Amazon #ad No live price right now. How this is funded |
| 3 | No image Pilot IC-100 cartridges, blue-black Pilot's own cartridge, sold twelve to a box, and the only cartridge that fits a Pilot fountain pen. | Refilling a Metropolitan, Kakuno or Prera | Check price on Amazon #ad No live price right now. How this is funded |
| 4 | No image Platinum Carbon Black cartridges The same permanent carbon ink as the bottle, in a cartridge, for a Preppy or Plaisir you actually carry. | Pigment ink without a bottle | Check price on Amazon #ad No live price right now. How this is funded |
1. Any pen that takes the standard cartridge
Monteverde international standard cartridges
The universal cartridge size, twelve to a pack, in the colors the original makers do not offer.
#ad No live price right now. How this is funded
The international standard cartridge is the closest thing this hobby has to a universal part. Kaweco, Jinhao, Faber-Castell, Diamine, J. Herbin and most European pens take it; Pilot, LAMY and Platinum do not.
Once your pen takes the standard size, the cartridge market opens up and you are no longer buying color from whoever made the pen.
Check the length: the standard comes in short and long, and a short-barrelled pocket pen only takes the short one.
| Format | 12 international standard cartridges per packSource: Monteverde international standard, black (retail listing, read 2026-09-01) |
|---|---|
| Fits | Pens that take international standard cartridgesSource: Monteverde international standard, black (retail listing, read 2026-09-01) |
| Colors | Black, blue, blue-black, burgundy, brown and others in the same sizeSource: Monteverde international standard, blue/black (retail listing, read 2026-09-01) |
| Published drying time | Not published |
What it does well
- Works across most non-proprietary pens
- Wide color range at a low price
- Twelve to a pack
What it does not
- Does not fit Pilot, LAMY or Platinum pens
- Short and long versions are easy to confuse
- No published performance figures
Skip this if your pen is a Pilot, a LAMY or a Platinum — none of them accept the standard cartridge.
2. Refilling a Safari, AL-star or Vista
LAMY T10 cartridges, black
The proprietary cartridge every LAMY fountain pen takes, and the only cartridge they take.
#ad No live price right now. How this is funded
The T10 is a proprietary size. An international standard cartridge will not fit a LAMY, and this is the single most common ordering mistake new Safari owners make.
At 1.25 ml each it holds more than a short international cartridge, which is a small consolation for the lock-in.
If you would rather use bottled ink, the LAMY Z28 converter fits the same barrel.
| Format | 5 cartridges per pack, 1.25 ml eachSource: LAMY T10 cartridges (retail listing, read 2026-09-01) |
|---|---|
| Fits | All LAMY fountain pen modelsSource: LAMY T10 cartridges (retail listing, read 2026-09-01) |
| Published drying time | Not published |
| Published water resistance | Not published |
What it does well
- Larger capacity than a short international cartridge
- Fits every LAMY fountain pen
- Nothing to measure or spill
What it does not
- Proprietary — no other brand's cartridges fit
- Costs more per milliliter than bottled ink
- Color choice is limited to LAMY's own range
Skip this if you own a Z28 converter and a bottle — cartridges cost several times as much per fill.
3. Refilling a Metropolitan, Kakuno or Prera
Pilot IC-100 cartridges, blue-black
Pilot's own cartridge, sold twelve to a box, and the only cartridge that fits a Pilot fountain pen.
#ad No live price right now. How this is funded
Pilot, like LAMY, uses its own cartridge size. If you own a Metropolitan, a Kakuno or a Prera, this is the refill, and an international standard cartridge will not go in.
Blue-black is the useful default: dark enough to read as serious, distinct enough from black to be legible in the margin of a printed page.
Twelve cartridges is roughly a year of light use.
| Format | 12 cartridges per packSource: Pilot Namiki IC100, blue/black (retail listing, read 2026-09-01) |
|---|---|
| Fits | Pilot fountain pens that take the IC-100 cartridgeSource: Pilot Namiki IC100, blue/black (retail listing, read 2026-09-01) |
| Also available | Black and blue, same pack sizeSource: Pilot Namiki IC100, black (retail listing, read 2026-09-01) |
| Published drying time | Not published |
What it does well
- Twelve per box, so it is a long time between orders
- Blue-black is a genuinely practical everyday color
- No mess and nothing to clean
What it does not
- Proprietary to Pilot
- Expensive per milliliter next to bottled ink
- Only three colors in common US circulation
Skip this if you have a CON-40 or CON-70 converter — a bottle costs far less per fill.
4. Pigment ink without a bottle
Platinum Carbon Black cartridges
The same permanent carbon ink as the bottle, in a cartridge, for a Preppy or Plaisir you actually carry.
#ad No live price right now. How this is funded
A pigment ink in cartridge form is genuinely useful: you get permanence without owning a bottle, and a Preppy with its slip-and-seal cap is unusually well suited to holding one.
The cleaning discipline still applies. Pigment dries hard, and a pen left inked and unused for a month is a cleaning job.
These are Platinum's proprietary size, so they fit Platinum pens only.
| Format | Platinum proprietary cartridges, blackSource: Platinum Carbon ink cartridges (retail listing, read 2026-09-01) |
|---|---|
| Type | Pigment ink, the cartridge form of Platinum Carbon BlackSource: Platinum Carbon Black bottle (retail listing, read 2026-09-01) |
| Published drying time | Not published |
| Published water resistance | Not published |
What it does well
- Permanent, water-resistant writing with no bottle needed
- Pairs well with Platinum's drying-resistant cap design
- Convenient for carrying
What it does not
- Proprietary to Platinum pens
- Needs more frequent flushing than dye ink
- Small capacity per cartridge
Skip this if your pen is not a Platinum, or if it regularly sits unused for weeks.
Short and long: the second trap
The international standard comes in two lengths. A long cartridge holds roughly twice what a short one does, and a short-barrelled pocket pen such as the Kaweco Sport only accepts the short version.
Full-size pens usually take either, and many will hold a spare short cartridge behind the one in use.
Cartridges versus a bottle
Cartridges cost several times as much per milliliter as bottled ink, and offer a small fraction of the color range. What they buy is convenience: nothing to spill, nothing to clean, and a spare that lives in a bag.
The usual pattern is cartridges to start, a converter once the pack runs out, and cartridges kept for travel afterwards. Cartridge vs converter works through the arithmetic.
Refilling a used cartridge
It works, and people do it. A blunt syringe fills an empty cartridge from a bottle, which gives you a converter's flexibility with a cartridge's shape — useful in pens where no converter fits.
It is fiddly, and the cartridge's seal degrades after a few cycles. Treat it as a workaround rather than a plan.
Questions people actually ask
Are all fountain pen cartridges the same?
No. Pilot, LAMY and Platinum each use a proprietary cartridge that nothing else fits. Most other brands use the international standard, which comes in short and long lengths.
What is an international standard ink cartridge?
A common cartridge size used by most European and Chinese pen makers, sold by many brands including Monteverde, Diamine and J. Herbin. It comes in a short version, for pocket pens, and a long version.
Can I put a LAMY cartridge in a Pilot pen?
No. Both are proprietary and they are different from each other. Neither accepts the international standard either.
Can you refill fountain pen cartridges?
Yes, with a blunt syringe and a bottle of ink. It works well enough as a workaround, particularly in pens where no converter fits, but the seal degrades after a few refills.
Are cartridges or bottled ink cheaper?
Bottled ink, by a wide margin per milliliter. Cartridges buy convenience rather than value — see cartridge vs converter.
Sources
- Monteverde international standard cartridges (retail listing, read 2026-09-01)
- LAMY T10 cartridges (retail listing, read 2026-09-01)
- Pilot Namiki IC100 cartridges (retail listing, read 2026-09-01)
- Platinum Carbon ink cartridges (retail listing, read 2026-09-01)
- Kaweco Sport mini converter (retail listing, read 2026-09-01)