Canon
EOS R6 Mark III
Hybrid 32.5MP full-frame RF body with 7K RAW video, 40fps electronic burst, 8.5-stop IBIS, and Dual Pixel CMOS AF II.
$2,799
Released Nov 2025
Pentax
K-3 Mark III
APS-C DSLR flagship with optical viewfinder and weather sealing.
$1,999
Released Apr 2021
EOS R6 Mark III is 4.5 years newer.
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Wins
EOS R6 Mark III
Wins
K-3 Mark III
6 categories tied
TL;DR — Key differences
- AEOS R6 Mark III has higher Max video bit rate (2600 Mbps vs 150 Mbps)
- AEOS R6 Mark III has higher AF points / zones (1053 vs 101)
- AEOS R6 Mark III has higher ISO max (native) (64,000 vs 25,600)
- AEOS R6 Mark III has higher Burst (electronic) (40 fps vs 20 fps)
- AEOS R6 Mark III has higher 4K max frame rate (120 fps vs 60 fps)
Key specs at a glance
Size and weight, to scale
EOS R6 Mark III
138 × 98 × 88 mm
699 g (1.54 lb / 24.66 oz)
K-3 Mark III
138 × 98 × 88 mm
520 g (1.15 lb / 18.34 oz)
EOS R6 Mark III and K-3 Mark III share virtually identical body dimensions.
EOS R6 Mark III is 179 g heavier than K-3 Mark III.
Depth (front-to-back): 88mm EOS R6 Mark III · 88mm K-3 Mark III
Back view, to scale
Width × Height — same proportions as the front of the body.
EOS R6 Mark III
138 × 98 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.
EOS R6 Mark III
138 × 88 mm
K-3 Mark III
138 × 88 mm
Sensor size, to scale
EOS R6 Mark III
35.9 × 23.9 mm · Full Frame
858 mm² area
K-3 Mark III
23.5 × 15.6 mm · APS-C
367 mm² area
2.3× larger sensor area = shallower depth of field and better low-light performance.
Lens ecosystem
Native lens selection
EOS R6 Mark III
✓ more lensesCanon RF
105+
native lenses available
K-3 Mark III
Pentax 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
EOS R6 Mark III
AF low-light limit
-6.5 EV vs -3 EV — lower is better
Subject recognition
Adds People, Dogs, Cats…
Dimensions (W×H×D mm)
Adds 138.4, 98.4, 88.4
Max video bit rate
2600 Mbps vs 150 Mbps — higher is better
AF points / zones
1053 vs 101 — higher is better
ISO max (native)
64,000 vs 25,600 — higher is better
Codecs
Adds CRM, XF-HEVC S, XF-AVC S
AA filter
Only EOS R6 Mark III supports it
Reasons to choose
K-3 Mark III
Subject recognition
Adds Human, Animal, Bird…
Dimensions (W×H×D mm)
Adds 138, 98, 88
Weight
520 g vs 699 g — lower is better
EVF magnification
0.78 × vs 0.76 × — higher is better
Both cameras share
- ✓ISO min (native) — Both 100
- ✓AF frame coverage — Both 100 %
- ✓Eye AF — Both support eye af
- ✓Animal / bird AF — Both support animal / bird af
- ✓Pre-Capture / Pre-Release — Both support pre-capture / pre-release
- ✓In-body stabilization — Both support in-body stabilization
Pros & cons at a glance
Editorially curated highlights and trade-offs.
EOS R6 Mark III
Pros
- ✓32.5MP full-frame sensor
- ✓7K RAW video & 4K 120p
- ✓40fps electronic burst with Pre-Continuous
- ✓8.5-stop IBIS
Cons
- –Single CFexpress Type B + SD slot
- –Smaller LCD than R5 II
- –LP-E6P required for full features
K-3 Mark III
Pros
- ✓Optical viewfinder
- ✓Weather sealed
- ✓IBIS in DSLR
Cons
- –DSLR system declining
- –APS-C
- –Limited video
Decided which one is right for you?
Compare live prices for the EOS R6 Mark III and K-3 Mark III at major authorized retailers.
Canon EOS R6 Mark III
Pentax K-3 Mark III
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Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for wildlife, EOS R6 Mark III or K-3 Mark III?
K-3 Mark III scores 10.0/10 versus 6.5/10 for EOS R6 Mark III — 20fps burst captures fleeting moments.
What's the resolution difference between the EOS R6 Mark III and K-3 Mark III?
EOS R6 Mark III is 32.5 MP and K-3 Mark III is 25.7 MP, so the EOS R6 Mark III captures more detail for cropping and large prints.
Do the EOS R6 Mark III and K-3 Mark III have in-body image stabilization?
EOS R6 Mark III has 8.5-stop in-body image stabilization, while k-3 Mark III has 7-stop in-body image stabilization.
Which shoots faster bursts — the EOS R6 Mark III or the K-3 Mark III?
EOS R6 Mark III reaches 40 fps electronic. K-3 Mark III reaches 20 fps electronic.
What's the weight difference between the EOS R6 Mark III and K-3 Mark III?
EOS R6 Mark III weighs 699 g and K-3 Mark III weighs 520 g, so the K-3 Mark III is 179 g lighter.
Do the EOS R6 Mark III and K-3 Mark III record 4K video?
EOS R6 Mark III: 4K up to 120p. K-3 Mark III: 4K up to 60p.
Are the EOS R6 Mark III and K-3 Mark III weather sealed?
EOS R6 Mark III: Yes. K-3 Mark III: Yes.
Which has better battery life?
Rated battery life is 640 shots (CIPA) for the EOS R6 Mark III and 640 shots for the K-3 Mark III, giving the K-3 Mark III the edge.
How much does each cost?
EOS R6 Mark III launched at $2,799 and K-3 Mark III at $1,999. The K-3 Mark III is $800 less.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed May 2026.
Product images courtesy of Canon and Pentax press materials.