Transparent converter of an Esterbrook fountain pen under a magnifying glass
Iguana Esterbrook

Pen Week 2026 · The Writing Lab

Filling
Test_

Every pen has its ritual.

Cartridge, converter, piston or plunger. The way a fountain pen is filled can transform our relationship with it. Discover the different filling systems and find the one that best suits the way you write.

Find your filling system TEST 04 / 06 · 30 OCTOBER

02 — The filling system

The same ink.
Different ways to begin.

Every fountain pen needs ink. But how it gets inside can be entirely different.

Some refill in seconds. Others invite us to open an ink bottle, work a mechanism and enjoy a small ritual.

Some systems are prized for their convenience, others for their versatility or their capacity.

Choosing a filling system isn’t just about understanding how it works. It also means discovering how we want to use our fountain pen.

01 — THE SYSTEMS

Four ways to enjoy ink.

Blue ink cartridge inside a transparent barrel
CartridgeSimplicity

A practical solution for those who value convenience. When the ink runs out, simply pop in a new cartridge and wait for it to flow again.

Ideal for everyday use, travel and anyone who prefers simple refilling.

Twist converter with blue ink
ConverterVersatility

A small refillable reservoir that lets you use bottled ink in many compatible fountain pens.

Perfect for those who enjoy exploring colours and changing inks.

Built-in piston mechanism with blue ink
PistonThe ritual

A built-in mechanism that lets you draw ink straight from the bottle.

An experience that combines function, engineering and the hands-on pleasure of every refill.

Plunger filling system with blue ink in a green resin fountain pen
PlungerStaying power

A plunger-driven vacuum filling system, found in fountain pens such as the Pilot Custom 823.

It can hold a generous supply of ink for those who enjoy long writing sessions.

Iguana Magazine · Writing guide

Cartridge, converter or piston?

Discover which filling system suits you.

From the convenience of cartridges to the generous capacity of plunger fillers. Learn how each mechanism works, its advantages and the details that can transform your writing experience.

Read the article
Converter and blue ink cartridge

03 — The experiment

Now it’s your turn.
Which filling system suits you?

You’ve seen the different ways to fill a fountain pen. Now it’s time to find out which system best suits your habits and the way you enjoy ink.

Filling Test · 3 questions

Three questions. Three choices.
One personalised recommendation.

  1. 01What do you prefer when refilling?
  2. 02How do you use your fountain pen?
  3. 03What do you value most?

04 — The results

Every way of writing
has its own ritual.

Discover the filling systems that may best suit your preferences.

Result 01 — Cartridge

The ease of writing without fuss.

You want a simple, practical experience.

Cartridges let you refill your fountain pen in moments, with no need to carry a bottle of ink.

Your trait Practicality

A selection for you · Filling system: Cartridge

We’ve selected fountain pens with filling systems that may suit the way you write.

Explore fountain pens
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Filling system: Cartridge · 01[Brand · Model][Price]
[Product photo]
Filling system: Cartridge · 02[Brand · Model][Price]
[Product photo]
Filling system: Cartridge · 03[Brand · Model][Price]
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Filling system: Cartridge · 04[Brand · Model][Price]

Your result is meant as a guide. Other mechanisms, such as plunger fillers, can be especially well suited to anyone who wants to write longer between refills.

05 — Iguana Personal Advisor

Your formula is personal.
So is our advice.

The Writing Lab tests are the starting point for discovering your preferences. But choosing a fountain pen also means finding the one that suits your hand, your writing and the way you like to use it.

Thinking of buying a fountain pen?

Our team of specialists can help you choose, with your needs, preferences and budget in mind.

ONLINE · BY APPOINTMENT

Speak to a specialist

Book an appointment with our team for personalised advice.

Book an appointment

06 — The Writing Lab · Special experience

Your handwriting says a lot about you.

Because everyone’s handwriting is as unique as they are.

At The Writing Lab we explore writing instruments, but there’s something that makes them truly personal: the way you write.

Graphology invites us to look at the strokes, slant and size of our letters and explore what they might suggest about our personality.

Discover what your handwriting says about you
Iguana Lab Graphology Laboratory card with a green Esterbrook fountain pen and the Pen Week 2026 brochure

Graphology offers interpretations for guidance only, not scientifically validated personality assessments.

07 — Analysis

The tests

Six ways to explore your writing. Find out which features suit you best through short interactive experiences.

Ruthenium-toned fountain pen nib
Test 01Tue 27

Nib Test

It all begins at the tip.

Find the nib that suits your hand.

Take the test
Orange and grey marbled resin cap
Test 02Wed 28

Material Test

Touch writes too.

Find the material that feels like you.

Take the test
Red resin fountain pen with gold clip
Test 03Thu 29

Design Test

Your style writes too.

Find the design that says who you are.

Take the test
Converter and gold nib
Test 04Fri 30

Filling Test

Every pen has its ritual.

Find your filling system.

Take the test
Bottle of gold ink
Test 05Sat 31

Ink Test

Bring colour to your words.

Find the ink that’s unmistakably you.

Take the test
Engraved metal cap and gold section of a fountain pen
Test 06Sun 1

Balance Test

Weight changes the feel.

Discover your ideal pen weight.

Take the test