Pentax
K-3 Mark III
APS-C DSLR flagship with optical viewfinder and weather sealing.
$1,999
Launch priceReleased Apr 2021
Pentax
K-5 IIs
APS-C flagship without AA filter for maximum sharpness — a cult favorite among Pentax stills shooters.
$1,099
Launch priceReleased Sep 2012
K-3 Mark III is 8.6 years newer.
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Wins
K-3 Mark III
Wins
K-5 IIs
11 categories tied
Which would you choose?
TL;DR — Key differences
- AK-3 Mark III has higher RAW buffer depth (120 frames vs 60 frames)
- AK-3 Mark III has higher Resolution (25.7 MP vs 16.3 MP)
- AK-3 Mark III has higher EVF resolution (3,690,000 vs 2,360,000)
- AK-3 Mark III has lower Weight (520 g vs 710 g)
- AK-3 Mark III has higher Burst (mechanical) (8 fps vs 6 fps)
Key specs at a glance
Size and weight, to scale
📸 Snap this size diff to shareK-3 Mark III
138 × 98 × 88 mm
520 g (1.15 lb / 18.34 oz)
Credit card
85.6 × 54 mm
for scale
K-5 IIs
131 × 97 × 73 mm
710 g (1.57 lb / 25.04 oz)
K-3 Mark III is 7mm wider, 1mm taller, and 15mm thicker than K-5 IIs.
K-3 Mark III is 190 g lighter than K-5 IIs.
Depth (front-to-back): 88mm K-3 Mark III · 73mm K-5 IIs
Sensor size, to scale
K-3 Mark III
23.5 × 15.6 mm · APS-C
367 mm² area
K-5 IIs
23.7 × 15.7 mm · APS-C
372 mm² area
Lens ecosystem
Native lens selection
K-3 Mark III
✓ more lensesPentax K
70+
native lenses available
K-5 IIs
✓ 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
K-3 Mark III
Dimensions (W×H×D mm)
Adds 138, 98, 88
RAW buffer depth
120 frames vs 60 frames — higher is better
Resolution
25.7 MP vs 16.3 MP — higher is better
EVF resolution
3,690,000 vs 2,360,000 — higher is better
Weight
520 g vs 710 g — lower is better
Burst (mechanical)
8 fps vs 6 fps — higher is better
Burst (electronic)
20 fps vs 15 fps — higher is better
IBIS effectiveness
7 stops vs 6 stops — higher is better
Reasons to choose
K-5 IIs
Dimensions (W×H×D mm)
Adds 131, 97, 73
Both cameras share
- ✓ISO min (native) — Both 100
- ✓ISO max (native) — Both 25,600
- ✓AF points / zones — Both 101
- ✓AF frame coverage — Both 100 %
- ✓Eye AF — Both support eye af
- ✓Animal / bird AF — Both support animal / bird af
Pros & cons at a glance
Editorially curated highlights and trade-offs.
K-3 Mark III
Pros
- ✓Optical viewfinder
- ✓Weather sealed
- ✓IBIS in DSLR
Cons
- –DSLR system declining
- –APS-C
- –Limited video
K-5 IIs
Pros
- ✓No AA filter
- ✓Weather sealed
- ✓Excellent build
- ✓Strong JPEG engine
Cons
- –16MP dated
- –Slow AF
- –DSLR declining
Decided which one is right for you?
Compare live prices for the K-3 Mark III and K-5 IIs at major authorized retailers.
Pentax K-3 Mark III
Pentax K-5 IIs
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Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for travel, K-3 Mark III or K-5 IIs?
K-3 Mark III scores 8.5/10 versus 6.5/10 for K-5 IIs — 520g — compact and travel-friendly.
What's the resolution difference between the K-3 Mark III and K-5 IIs?
K-3 Mark III is 25.7 MP and K-5 IIs is 16.3 MP, so the K-3 Mark III captures more detail for cropping and large prints.
Do the K-3 Mark III and K-5 IIs have in-body image stabilization?
K-3 Mark III has 7-stop in-body image stabilization, while K-5 IIs has 6-stop in-body image stabilization.
Which shoots faster bursts — the K-3 Mark III or the K-5 IIs?
K-3 Mark III reaches 20 fps electronic. K-5 IIs reaches 15 fps electronic.
What's the weight difference between the K-3 Mark III and K-5 IIs?
K-3 Mark III weighs 520 g and K-5 IIs weighs 710 g, so the K-3 Mark III is 190 g lighter.
Do the K-3 Mark III and K-5 IIs record 4K video?
K-3 Mark III: 4K up to 60p. K-5 IIs: 4K up to 60p.
Are the K-3 Mark III and K-5 IIs weather sealed?
K-3 Mark III: Yes. K-5 IIs: Yes.
Which has better battery life?
Rated battery life is 640 shots (CIPA) for the K-3 Mark III and 640 shots for the K-5 IIs, giving the K-5 IIs the edge.
How much does each cost?
K-3 Mark III launched at $1,999 and K-5 IIs at $1,099. The K-5 IIs is $900 less.
Can't decide between two? Compare a third camera.
Add any camera to get a three-way K-3 Mark III vs K-5 IIs vs X comparison.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed June 2026.