Custom Vocabulary for Voice Typing: Train Your Words
Discover how to teach speech recognition your industry jargon, proper names, and technical terms. Learn browser limitations, desktop solutions, and practical workarounds for accurate dictation.
Table of Contents
- • Why Custom Vocabulary Matters
- • How Vocabulary Training Works
- • Browser API Limitations
- • Desktop Solutions & Training
- • Practical Workarounds
- • Industry-Specific Strategies
- • Frequently Asked Questions
Last updated: November 12, 2025
Why Custom Vocabulary Matters
Speech recognition systems are trained on billions of common words, but they struggle with specialized terminology. Understanding when and why custom vocabulary is needed helps you choose the right voice typing solution.
Medical Professionals
Medical jargon includes thousands of terms not in everyday vocabulary: "cholecystectomy," "arrhythmia," "epinephrine." Standard speech recognition transcribes these as gibberish.
Common Misrecognitions:
- • "colonoscopy" → "cologne ah scopy"
- • "acetaminophen" → "a set a mean off in"
- • "stethoscope" → "step those cope"
Legal Professionals
Legal terminology includes Latin phrases, case citations, and formal language that confuses standard models: "habeas corpus," "res judicata," "voir dire."
Common Misrecognitions:
- • "subpoena" → "sub Pina"
- • "pro bono" → "pro bone oh"
- • "affidavit" → "after David"
Developers & Tech
Programming includes frameworks, libraries, and acronyms that aren't in standard dictionaries: "React," "Kubernetes," "PostgreSQL," "asyncio."
Common Misrecognitions:
- • "Kubernetes" → "Cooper Nettie's"
- • "PyTorch" → "pie torch"
- • "OAuth" → "oh off"
Proper Names
Unique names, especially non-English origins, are consistently misrecognized: "Siobhan," "Tchaikovsky," "Nguyen," company names like "Anthropic."
Common Misrecognitions:
- • "Siobhan" → "she Von"
- • "Anthropic" → "an tropic"
- • "Nguyen" → "new win"
Impact on Productivity: Users report spending 20-40% of dictation time correcting technical terms and proper names when using speech recognition without custom vocabulary. Custom dictionaries can reduce correction time by 80-90%.
How Vocabulary Training Works
Custom vocabulary training modifies speech recognition models to recognize specialized terms. Understanding the technical process helps set realistic expectations for accuracy improvements.
The Training Process
Step 1: Word Addition
You provide the custom word in text form: "Kubernetes" or "Siobhan." Advanced systems let you specify pronunciation phonetically: "koo-ber-NEH-teez" or "shi-VAWN."
Step 2: Audio Samples (Optional)
Some systems (Dragon, Windows Speech) ask you to speak the word 3-5 times. This trains the model on your specific pronunciation, accent, and voice characteristics.
Step 3: Phonetic Mapping
The system generates phonetic representations of the word using IPA (International Phonetic Alphabet) or language-specific phoneme sets. This helps the acoustic model recognize the sound pattern.
Step 4: Language Model Update
The word is added to the language model's vocabulary with appropriate probability weights. Context clues help: "administered acetaminophen" is more likely than "administered a set a mean off in."
Step 5: Continuous Learning
As you use the custom word in dictation, the system tracks corrections. If you frequently change "Cooper Nettie's" to "Kubernetes," the model learns and improves accuracy over time.
✅ What Training Improves
- ✓ Recognition of specific technical terms you add
- ✓ Proper names and unique vocabulary
- ✓ Acronyms and abbreviations
- ✓ Brand names and product terminology
- ✓ Industry-specific jargon you use frequently
❌ What Training Doesn't Fix
- ✗ Accent-related misrecognitions of common words
- ✗ Background noise or poor microphone quality
- ✗ Homophones (words that sound identical)
- ✗ Words you haven't explicitly added
- ✗ Grammar and punctuation errors
Works in your browser. No sign-up. Audio processed locally.
Transcript
Tip: Keep the tab focused, use a good microphone, and speak clearly. Accuracy depends on your browser and device.
Browser API Limitations
The Web Speech API used by browser-based voice typing tools has significant limitations regarding custom vocabulary. Understanding these constraints helps set appropriate expectations.
🚫 No Custom Vocabulary Support
The Web Speech API does not provide any mechanism for adding custom words, training pronunciation, or modifying the underlying speech recognition model. This is a fundamental limitation of the API specification, not specific to any implementation.
Why this limitation exists:
- • Speech models run on cloud servers (Google/Apple), not in your browser
- • Modifying server-side models would require per-user customization (billions of users)
- • Training requires significant computational resources not available in browsers
- • Security/privacy concerns about letting websites modify speech recognition
Alternative: Use Phonetic Spelling
When dictating with browser tools, spell out difficult words phonetically: say "cooper netties" and manually correct to "Kubernetes." Over time, you'll develop a mental map of how to pronounce words for accurate recognition.
Alternative: Context Helps
Provide surrounding context: instead of saying "acetaminophen" in isolation, say "the patient was given acetaminophen for pain." Context clues help the model disambiguate technical terms.
Alternative: Post-Processing Scripts
Advanced users can write find-replace scripts: automatically convert "cooper Nettie's" → "Kubernetes" after dictation. Tools like AutoHotkey, Keyboard Maestro, or TextExpander enable this workflow.
Recommendation: If custom vocabulary is critical for your work (medical, legal, technical), use desktop speech recognition software like Dragon NaturallySpeaking, Windows Speech Recognition, or Apple Dictation instead of browser-based tools.
Desktop Solutions & Training
Desktop speech recognition software offers robust custom vocabulary features. Here's how each major platform handles vocabulary training.
🐉 Dragon NaturallySpeaking
Industry leader for custom vocabulary
Vocabulary Editor
Access via Tools → Vocabulary Editor. Add unlimited custom words with optional pronunciation training. Supports written form + spoken form (e.g., "Dr." spoken as "doctor").
Audio Training
Dragon asks you to speak each custom word 3 times. Analyzes your pronunciation, accent, and voice characteristics to build personalized acoustic models. Accuracy improves 90-95% after training.
Industry Vocabularies
Dragon Medical, Dragon Legal include pre-loaded specialized dictionaries with 30,000+ terms. Reduces setup time significantly for professionals.
Import/Export
Export custom vocabularies as .dxp files. Share with colleagues or backup for disaster recovery. Import industry-specific dictionaries from Dragon marketplace.
Cost: $200-$500 (Medical/Legal: $1,500+)
🪟 Windows Speech Recognition
Built-in Windows solution
Speech Dictionary
Access via Control Panel → Speech Recognition → Open Speech Dictionary. Add words manually but no pronunciation training available. Limited compared to Dragon.
Automatic Learning
Windows analyzes your emails, documents, and searches to automatically expand vocabulary. Privacy-conscious users can disable this in Settings → Privacy → Speech.
Correction Learning
When you correct misrecognitions, Windows remembers and improves. Say "correct that" to fix errors and train the model simultaneously.
Cost: Free (included with Windows)
🍎 Apple Dictation
macOS/iOS built-in dictation
No Manual Vocabulary Editor
Apple does not provide a user-accessible vocabulary editor. You cannot manually add words like Dragon or Windows. This is a deliberate design choice.
Automatic Context Learning
Apple's speech recognition learns from your Contacts, Calendar, Notes, Messages, and Mail. Proper names you use frequently are automatically added to vocabulary. No manual intervention required.
Text Replacement Workaround
Use System Preferences → Keyboard → Text to create shortcuts. Dictate phonetic spelling, auto-expands to correct term. E.g., "kubr" → "Kubernetes".
Cost: Free (included with macOS/iOS)
🔧 Open Source: Vosk, Whisper
Advanced developer solutions
Custom Model Training
Vosk and Whisper allow full model customization if you have technical expertise. Fine-tune models on your specific vocabulary dataset (requires Python, ML knowledge, and GPU hardware).
Language Model Modification
Edit language model files directly to add words with probability weights. Technical but powerful. See Vosk and Whisper documentation for details.
Cost: Free (requires technical skills)
Practical Workarounds
If you're stuck with browser-based voice typing but need better handling of specialized terms, these workarounds help bridge the gap.
1. Text Expansion Tools
Combine voice typing with text expanders to automatically fix common misrecognitions.
TextExpander (Mac/Win)
Create snippet: "kubr" expands to "Kubernetes." Dictate phonetic, auto-corrects. $40/year.
AutoHotkey (Win)
Free scripting tool. Write rules: ::kubr::Kubernetes. Instant correction after dictating.
Keyboard Maestro (Mac)
Powerful automation. Trigger text replacement when specific phrases detected. $36 one-time.
2. Find & Replace Macros
After dictating, run find-replace operations to correct common errors in bulk.
Example workflow:
- 1. Dictate full document with known misrecognitions
- 2. Copy to Word or text editor
- 3. Run saved find-replace macro: "cooper Nettie's" → "Kubernetes", "pie torch" → "PyTorch"
- 4. Fix 90% of technical terms in 5 seconds
3. Hybrid Dictation Strategy
Use browser voice typing for general content, switch to desktop software for technical sections.
Best practices:
- • Browser tools: Introductions, conclusions, explanations, summaries
- • Desktop tools (Dragon): Technical procedures, diagnosis, legal terminology, code
- • Combine in final document for best accuracy across all content types
4. Spell Out & Correct Pattern
Develop consistent phonetic pronunciations for your most-used technical terms.
Example pronunciations:
- • Kubernetes → "Cooper netties" (then correct to proper spelling)
- • PostgreSQL → "post gress Q L"
- • acetaminophen → "uh-see-tuh-MIN-oh-fen" (exaggerate syllables)
- • OAuth → "oh auth" (pause slightly between words)
Industry-Specific Strategies
Different professions face unique vocabulary challenges. Here are targeted strategies for common industries.
🏥 Medical
- Solution: Dragon Medical One (cloud) or Dragon Medical Practice Edition (desktop)
- Vocabulary: 300,000+ medical terms pre-loaded
- Training: Specialty-specific models (radiology, pathology, surgery, etc.)
- ROI: Saves 2-3 hours/day on documentation for most physicians
- Cost: $1,500-$3,000 + training time
⚖️ Legal
- Solution: Dragon Legal Individual or Professional
- Vocabulary: 40,000+ legal terms, case citations, Latin phrases
- Training: Practice area templates (litigation, contracts, real estate)
- ROI: Reduces transcription costs by 70-80%
- Cost: $500-$1,500 for individual license
💻 Software Development
- Solution: Talon + custom command grammars
- Vocabulary: Custom dictionaries for frameworks, libraries, APIs
- Training: Community-shared configs for Python, JavaScript, Go, Rust
- ROI: Prevents/recovers from RSI while maintaining 80%+ coding speed
- Cost: Free (Talon) or $99/year (Talon Pro)
📚 Academia & Research
- Solution: Dragon Professional + custom vocabulary lists
- Vocabulary: Field-specific terminology (biology, chemistry, sociology, etc.)
- Training: Import glossaries from textbooks and journals
- ROI: Accelerates paper writing and note-taking by 3-5x
- Cost: $300-$500 (academic discounts available)
📞 Customer Service
- Solution: Cloud transcription APIs (Google, Azure) with custom models
- Vocabulary: Product names, SKUs, company-specific terms
- Training: Fine-tune models on recorded calls and transcripts
- ROI: Automated transcription reduces review time by 90%
- Cost: $0.006-$0.024 per minute of audio
🔬 Scientific Research
- Solution: Dragon Professional + domain-specific vocabulary imports
- Vocabulary: Chemical compounds, gene names, equipment terminology
- Training: Create lab-specific dictionaries shared across research team
- ROI: Streamlines lab notes and protocol documentation
- Cost: $300-$500 per license
Frequently Asked Questions
Can I add custom words to Voice to Text Online?
No. Voice to Text Online uses the browser's Web Speech API, which does not support custom vocabulary. This is a limitation of the API itself, not our implementation. For custom vocabulary, you need desktop software like Dragon NaturallySpeaking, Windows Speech Recognition, or specialized tools like Dragon Medical for medical terminology.
How many custom words can I add to Dragon?
Dragon supports unlimited custom vocabulary entries. However, practical limits exist: adding 10,000+ words may slow down recognition slightly. Most users add 50-500 custom terms. Dragon Medical/Legal editions come pre-loaded with 30,000-300,000 specialized terms, so you typically only need to add your specific proper names and company-specific jargon.
Does Google Docs support custom vocabulary?
No. Google Docs voice typing uses the same Web Speech API as Voice to Text Online, which lacks custom vocabulary support. However, you can use Google Docs' substitution feature (Tools → Preferences → Substitutions) to automatically replace misrecognized terms after dictation. For example, auto-replace "cooper Nettie's" with "Kubernetes" every time it appears.
How long does it take to train Dragon on new vocabulary?
Adding a single word takes 30-60 seconds including pronunciation training (speak the word 3 times). Bulk imports from text files are faster: 1,000 words in 2-3 minutes, but without pronunciation training. Dragon's automatic learning improves accuracy continuously as you use it, with noticeable improvements after 2-3 hours of dictation.
Can I share custom vocabulary with my team?
Yes, if using Dragon Professional or higher. Export your custom vocabulary as a .dxp file (Tools → Manage Vocabularies → Export) and share with colleagues. They can import into their Dragon installation. Dragon Legal and Medical Professional editions support centralized vocabulary management for teams. Windows Speech Recognition and Apple Dictation do not support vocabulary sharing.
Related Resources
Try General Purpose Voice Typing
While Voice to Text Online doesn't support custom vocabulary, it excels at dictating everyday content. Try it free for emails, notes, and general writing. For specialized terminology, explore our desktop software recommendations.
Start Dictating Now →