10 Tips to Improve Speech-to-Text Accuracy on Mac

Speech-to-text accuracy has improved dramatically, but it's not magic. Your environment, equipment, and technique all affect results. Here are 10 proven tips to get the best transcription accuracy.

1. Use a Quality Microphone

Your Mac's built-in mic works, but dedicated microphones make a significant difference:

• AirPods/AirPods Pro: Excellent for casual use, good noise isolation
• USB Headset: Consistent positioning, noise cancellation
• Lapel Mic: Great for hands-free, close to mouth
• Desktop Condenser: Studio quality but picks up room noise

Pro tip: AirPods Pro with noise cancellation active are surprisingly excellent for dictation.

2. Optimize Your Environment

Background noise is the enemy of accuracy:

• Close windows to reduce street noise
• Turn off fans, AC, or noisy appliances nearby
• Use a room with soft surfaces (carpet, curtains) to reduce echo
• Face away from noise sources

3. Speak Clearly, Not Slowly

Common mistake: speaking unnaturally slow. Modern AI models are trained on natural speech. Speak at your normal pace, but:

• Enunciate clearly (don't mumble)
• Maintain consistent volume
• Avoid trailing off at end of sentences
• Pause briefly between distinct thoughts

4. Use a Custom Dictionary

Technical terms, names, and jargon trip up speech recognition. Apps like Sotto let you add custom vocabulary:

• Company and product names
• Technical acronyms (API, SDK, JWT)
• Framework names (Next.js, SwiftUI)
• Colleague names
• Industry-specific terminology

A well-trained dictionary can improve accuracy by 20-30% for specialized content.

5. Choose the Right Model Size

Whisper comes in different sizes. Bigger isn't always better:

• Tiny: Fast, good for quick notes
• Base: Good balance of speed and accuracy
• Small: Better accuracy, slight delay
• Medium: High accuracy, more processing time
• Large: Best accuracy, requires more RAM

For real-time dictation, Tiny or Base often provide the best experience.

6. Know Your Punctuation Commands

Speaking punctuation gets you cleaner output:

• "period" → .
• "comma" → ,
• "question mark" → ?
• "exclamation point" → !
• "new line" → line break
• "new paragraph" → double line break
• "colon" → :
• "semicolon" → ;

7. Warm Up Your Voice

First thing in the morning, your voice may be unclear. Before important dictation:

• Drink water (hydrated vocal cords perform better)
• Do some light speaking to warm up
• Clear your throat if needed

8. Position Your Microphone Correctly

Microphone placement matters:

• Distance: 2-6 inches from mouth for most mics
• Angle: Slightly off-axis to reduce plosives (p, b sounds)
• Consistency: Keep the same position throughout

9. Use Cloud Models for Difficult Content

Local models are great for privacy and speed, but cloud APIs (OpenAI, Groq) can handle tricky situations better:

• Heavy accents
• Multiple speakers
• Technical/medical terminology
• Background noise

Apps like Sotto let you switch between local and cloud on the fly.

10. Review and Correct Consistently

No transcription is 100% accurate. Build a habit of quick review:

• Glance at output after each dictation
• Fix errors immediately (muscle memory)
• Add commonly misrecognized words to your dictionary
• Note patterns (certain words always wrong → add to dictionary)

Accuracy Expectations

With good conditions and technique, expect:

• 95-98% accuracy for clear speech, common words
• 90-95% accuracy for technical content with trained dictionary
• 85-90% accuracy for difficult conditions or accents

Even at 95%, you'll spend less time correcting than you would typing from scratch.