Fujifilm
X100VI
Fixed-lens premium compact with 40MP X-Trans and classic street photography design.
$1,599
Released Feb 2024
Pentax
K-3 Mark III
APS-C DSLR flagship with optical viewfinder and weather sealing.
$1,999
Released Apr 2021
X100VI is 2.8 years newer.
Wins
X100VI
Wins
K-3 Mark III
4 categories tied
TL;DR — Key differences
- AX100VI has higher AF points / zones (425 vs 101)
- BK-3 Mark III has higher RAW buffer depth (120 frames vs 52 frames)
- BK-3 Mark III has higher Battery life (CIPA) (640 shots vs 310 shots)
- BK-3 Mark III has higher ISO max (native) (25,600 vs 12,800)
- BK-3 Mark III has higher Card slots (2 vs 1)
Key specs at a glance
Size and weight, to scale
X100VI
128 × 75 × 55 mm
521 g (1.15 lb / 18.38 oz)
K-3 Mark III
138 × 98 × 88 mm
520 g (1.15 lb / 18.34 oz)
X100VI is 10mm narrower, 23mm shorter, and 33mm thinner than K-3 Mark III.
X100VI is 1 g heavier than K-3 Mark III.
Depth (front-to-back): 55mm X100VI · 88mm K-3 Mark III
Back view, to scale
Width × Height — same proportions as the front of the body.
X100VI
128 × 75 mm
K-3 Mark III
138 × 98 mm
Top view, to scale
Width × Depth (front-to-back) — see which body is chunkier on the table.
X100VI
128 × 55 mm
K-3 Mark III
138 × 88 mm
Sensor size, to scale
X100VI
23.5 × 15.7 mm · APS-C
369 mm² area
K-3 Mark III
23.5 × 15.6 mm · APS-C
367 mm² area
Lens ecosystem
Native lens selection
X100VI: mount data unavailable
K-3 Mark III
✓ more lensesPentax K
70+
native lenses available
Counts include current first-party and major third-party native autofocus lenses.
Use-case scoring
Which one for what?
Algorithmic scores from verified specs · 10 = best in class
Why pick one over the other
Reasons to choose
X100VI
Dimensions (W×H×D mm)
Adds 128, 74.8, 55.3
Card types
Adds SD UHS-I
AF points / zones
425 vs 101 — higher is better
Subject recognition
Adds Automobile, Motorcycle/Bike, Airplane…
Resolution
40.2 MP vs 25.7 MP — higher is better
Max video bit rate
200 Mbps vs 150 Mbps — higher is better
Reasons to choose
K-3 Mark III
Dimensions (W×H×D mm)
Adds 138, 98, 88
Card types
Adds SD UHS-II
RAW buffer depth
120 frames vs 52 frames — higher is better
Battery life (CIPA)
640 shots vs 310 shots — higher is better
ISO max (native)
25,600 vs 12,800 — higher is better
Subject recognition
Adds Human, Vehicle
Card slots
2 vs 1 — higher is better
Headphone jack (3.5mm)
Only K-3 Mark III supports it
Both cameras share
- ✓AF frame coverage — Both 100 %
- ✓Eye AF — Both support eye af
- ✓Animal / bird AF — Both support animal / bird af
- ✓Burst (electronic) — Both 20 fps
- ✓Pre-Capture / Pre-Release — Both support pre-capture / pre-release
- ✓4K max frame rate — Both 60 fps
Pros & cons at a glance
Editorially curated highlights and trade-offs.
X100VI
Pros
- ✓Unique fixed 23mm lens
- ✓40MP sensor
- ✓Film simulations
- ✓Compact street camera
Cons
- –Fixed lens only
- –No interchangeable lenses
- –Premium price
K-3 Mark III
Pros
- ✓Optical viewfinder
- ✓Weather sealed
- ✓IBIS in DSLR
Cons
- –DSLR system declining
- –APS-C
- –Limited video
Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for video, X100VI or K-3 Mark III?
K-3 Mark III scores 6.0/10 versus 4.0/10 for X100VI — 4K recording.
What's the resolution difference between the X100VI and K-3 Mark III?
X100VI is 40.2 MP and K-3 Mark III is 25.7 MP, so the X100VI captures more detail for cropping and large prints.
Do the X100VI and K-3 Mark III have in-body image stabilization?
X100VI has 6-stop in-body image stabilization, while k-3 Mark III has 7-stop in-body image stabilization.
Which shoots faster bursts — the X100VI or the K-3 Mark III?
X100VI reaches 20 fps electronic. K-3 Mark III reaches 20 fps electronic.
What's the weight difference between the X100VI and K-3 Mark III?
X100VI weighs 521 g and K-3 Mark III weighs 520 g, so the K-3 Mark III is 1 g lighter.
Do the X100VI and K-3 Mark III record 4K video?
X100VI: 4K up to 60p. K-3 Mark III: 4K up to 60p.
Are the X100VI and K-3 Mark III weather sealed?
X100VI: Yes. K-3 Mark III: Yes.
Which has better battery life?
Rated battery life is 310 shots (CIPA) for the X100VI and 640 shots for the K-3 Mark III, giving the K-3 Mark III the edge.
How much does each cost?
X100VI launched at $1,599 and K-3 Mark III at $1,999. The X100VI is $400 less.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed May 2026.
Product images courtesy of Fujifilm and Pentax press materials.