1st Note

Casio

Casio CT-S400 Review

600 sounds plus Bluetooth — the CT-S300's smarter sibling

MSRP

$230

Source: Manufacturer (2026-04)

61 Keys 4 kg non weighted Bluetooth Beginner

Scores

10.0 6.0 10.0 0.8 7.2 Beginner Night Practice Portability Touch Reality Value

Beginner

10.0

Night Practice

6.0

Portability

10.0

Touch Reality

0.8

Value

7.2
How These Scores Were Calculated

Beginner

10.0
Factor This Piano Points
Base Score 3.0
Lesson Function Yes +1.5
App Connectivity Yes +1.5
Recording Yes +1
Metronome Yes +0.5
Transpose Yes +0.3
Layer / Split Yes +0.3
Preset Songs 60 +1.5
Sound Variety 600 sounds +0.5

Night Practice

6.0
Factor This Piano Points
Base Score 2.0
Headphone Jacks 1 +1
Headphone Type 3.5mm +0.5
Headphone Optimization No +0
Key Action Quietness non weighted +1.5
Volume Control Yes +1
Bluetooth Audio No +0

Portability

10.0
Factor This Piano Points
Base Score 5.0
Weight 4 kg +3
Width 930 mm +1
Battery Yes +1.5
Foldable No +0
Key Count 61 keys +0.5

Touch Reality

0.8
Factor This Piano Points
Key Action Quality non weighted (grade 1) +0.6
Key Count 61 keys +0.2
Polyphony 48 notes +0
Sound Modeling No +0
Key Surface matte +0

Our Verdict

The CT-S400 takes everything the CT-S300 does well — portability, fun, variety — and adds Bluetooth MIDI, 600 sounds, and a more capable AiX sound engine. If you want a versatile, connected mini keyboard without spending much, this is the one.

Pros

  • 600 built-in sounds with AiX Sound Source — richer, more detailed tones than the CT-S300
  • Bluetooth MIDI — connect wirelessly to apps and music software
  • Battery powered (6×AA) at only 4.0 kg — go-anywhere portability
  • Chordana Play app connectivity for guided learning
  • 200 built-in rhythms for accompaniment and practice
  • Dance Music Mode with expanded options
  • USB MIDI for wired computer connectivity
  • Built-in lesson function with step-up system

Cons

  • Non-weighted keys — no piano feel
  • Only 61 keys — insufficient for serious piano study
  • 48-note polyphony — can struggle with layered sounds
  • Single 3.5mm headphone jack
  • No Bluetooth audio — MIDI only, can't stream music to speakers
  • 5W speakers are quiet — fine for personal practice, not for performing
  • $60 more than the CT-S300 for similar core experience

The CT-S400 is the smarter version of Casio's popular CT-S300. The Bluetooth MIDI is the headline upgrade — connecting wirelessly to apps and music software opens up possibilities that wired-only keyboards can't match. The jump from 400 to 600 sounds and the improved AiX engine mean the tones are noticeably richer too. At $230, it's still firmly in budget territory. The same caveats apply: no weighted keys, no piano feel, 48-note polyphony. But if you want a fun, portable, connected keyboard for casual music-making and learning, the CT-S400 is the best value in Casio's mini lineup.

Technical Deep Dive

About the Key Action

The keys are identical in feel to the CT-S300 — completely unweighted with no resistance or grading. They're light, fast, and easy on the fingers, which is comfortable for exploring the 600 sounds and playing casually. But they don't simulate a piano in any way. If you're trying to develop proper piano technique, you need weighted keys. This keyboard is designed for musical exploration, not piano practice.

Who Is This Piano For?

You want a bit more than the CT-S300 — specifically wireless connectivity and a wider palette of sounds — but you're still firmly in the 'exploration and fun' category rather than serious piano study. Maybe you're an aspiring music producer who wants a lightweight MIDI controller that also works standalone. Maybe you want to connect to iPad apps wirelessly for interactive learning. The Bluetooth MIDI adds a layer of convenience that makes the CT-S400 genuinely more useful as a modern music tool.

Specifications

Keys 61
Key Action Non Weighted
Polyphony 48 notes
Sounds 600
Weight 4 kg
Speakers 5W (×2)
Bluetooth MIDI

Recommended Accessories

🪑

Stand

Stand not included (sold separately)

A sturdy X-stand or furniture-style stand is essential if one isn't included.

🎧

Headphones

Closed-back headphones with good bass response make practice sessions more enjoyable.

🎹

Sustain Pedal

The included pedal is usually basic. A half-damper pedal upgrade is worthwhile for expressive playing.

💺

Bench

An adjustable-height bench helps maintain proper posture during long practice sessions.

Where to Buy

Casio CT-S400 $230

How It Compares

CT-S400 vs CT-S300

The CT-S300 edges ahead in Value. The CT-S300 costs $60 less. Choose the CT-S300 if you prioritize value for money.

Casio CT-S300 →

CT-S400 vs PSR-E373

The CT-S400 scores higher in Beginner and Value, while the PSR-E373 edges ahead in Night Practice and Touch Reality. Choose the CT-S400 if you prioritize beginner-friendly features.

Yamaha PSR-E373 →

CT-S400 vs NP-35

The CT-S400 scores higher in Beginner and Portability and Value, while the NP-35 edges ahead in Touch Reality. Choose the CT-S400 if you prioritize beginner-friendly features.

Yamaha NP-35 →

Frequently Asked Questions

Is the Casio CT-S400 good for beginners?

Yes. The Casio CT-S400 scores 10/10 on our Beginner scale, which means it has strong learning features like lesson modes, app connectivity, and built-in songs to help new players get started.

Does the Casio CT-S400 have Bluetooth?

The Casio CT-S400 has Bluetooth MIDI for wireless app connectivity, but no Bluetooth Audio for streaming music.

How heavy is the Casio CT-S400?

The Casio CT-S400 weighs 4 kg (9 lbs). It scores 10/10 on our Portability scale. This is light enough to carry between rooms or to lessons.

Can I use headphones with the Casio CT-S400?

Yes. The Casio CT-S400 has 1 headphone jack (3.5mm). It scores 6/10 on our Night Practice scale.

How many keys does the Casio CT-S400 have?

The Casio CT-S400 has 61 keys, which is smaller than a standard 88-key piano. This is fine for beginners and casual playing, but advanced pieces may require more range.

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