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10 min readBrassTranscripts Team

AssemblyAI vs Deepgram: API Pricing for High Volume

AssemblyAI and Deepgram are the two dominant "developer-first" speech-to-text APIs. Both offer per-minute pricing, both require API integration, and both charge separately for features like speaker identification and content analysis. For teams processing hundreds or thousands of hours monthly, the cost difference between these two APIs adds up fast.

This comparison uses verified pricing from AssemblyAI's pricing page and Deepgram's pricing page as of March 2026. We break down real costs at scale — not just base rates, but what you actually pay when you enable the features most teams need.

For individual deep-dives on each provider, see our AssemblyAI pricing breakdown and Deepgram pricing breakdown.

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Base Transcription Pricing

AssemblyAI Universal-2 starts at $0.15/hour while Deepgram Nova-3 starts at $0.46/hour on Pay-As-You-Go — a 3x difference at base rates before any add-on features.

Both APIs charge per minute of audio processed, but the model tiers and pricing structures differ significantly.

AssemblyAI Base Rates

AssemblyAI offers multiple model tiers at different price points (source: AssemblyAI pricing):

Model Pre-recorded Streaming
Universal-2 $0.15/hr ($0.0025/min) $0.15/hr
Universal-3 Pro $0.21/hr ($0.0035/min) $0.45/hr

Deepgram Base Rates

Deepgram's pricing varies by model and payment plan (source: Deepgram pricing):

Model Pay-As-You-Go Growth Plan
Nova-3 Monolingual $0.46/hr ($0.0077/min) $0.39/hr ($0.0065/min)
Nova-3 Multilingual $0.55/hr ($0.0092/min) $0.47/hr ($0.0078/min)
Nova-2 $0.35/hr ($0.0058/min) $0.28/hr ($0.0047/min)

Head-to-Head: Base Rate Only

At first glance, AssemblyAI looks cheaper — $0.15/hour for Universal-2 vs Deepgram's $0.46/hour for Nova-3. That's a 3x difference on base rate alone.

But base rate comparisons are misleading. Most production deployments need speaker identification, and many need content intelligence features. That's where the math changes.

The Add-On Tax: Real Cost with Features

Neither AssemblyAI nor Deepgram includes speaker identification in the base price — both charge it as a paid add-on, unlike BrassTranscripts which bundles speaker ID into flat-rate pricing.

Both APIs charge separately for features beyond basic transcription. Here's what a typical production deployment costs.

Typical Production Setup: Transcription + Speaker ID

Feature AssemblyAI Deepgram
Base transcription $0.15/hr (Universal-2) $0.46/hr (Nova-3)
Speaker diarization +$0.02/hr +$0.12/hr ($0.002/min)
Total $0.17/hr $0.58/hr
Feature AssemblyAI Deepgram
Base transcription $0.15/hr $0.46/hr
Speaker diarization +$0.02/hr +$0.12/hr
Sentiment analysis +$0.02/hr Not available
Summarization +$0.03/hr Not available
Entity detection +$0.08/hr Not available
Total $0.30/hr $0.58/hr

AssemblyAI offers more audio intelligence features as paid add-ons. Deepgram focuses on core transcription speed and accuracy, with fewer post-processing features built into the API.

Key takeaway: AssemblyAI is cheaper per hour even with add-ons enabled, but the price gap narrows as you stack features. At base + speaker ID only, AssemblyAI costs $0.17/hr vs Deepgram's $0.58/hr.

Volume Cost Comparison: 100 to 10,000 Hours

AssemblyAI costs roughly 3x less than Deepgram at every volume tier when both include speaker identification — processing 10,000 hours/month costs $1,700 with AssemblyAI vs $5,100 with Deepgram. BrassTranscripts offers a third option for teams without developers: flat-rate pricing at $2.50–$6.00 per file with speaker ID included.

Here's what each API costs at common volume tiers, using the most typical production configuration (transcription + speaker identification).

AssemblyAI (Universal-2 + Speaker ID = $0.17/hr)

Monthly Volume Monthly Cost Cost per Minute
100 hours $17 $0.0028
500 hours $85 $0.0028
1,000 hours $170 $0.0028
5,000 hours $850 $0.0028
10,000 hours $1,700 $0.0028

Deepgram (Nova-3 + Speaker ID)

Monthly Volume Plan Monthly Cost Cost per Minute
100 hours Pay-As-You-Go $58 $0.0097
500 hours Growth $255 $0.0085
1,000 hours Growth $510 $0.0085
5,000 hours Growth $2,550 $0.0085
10,000 hours Growth $5,100 $0.0085

Deepgram Growth plan pricing assumes $4,000+/year pre-paid commitment with ~16% discount on Nova-3.

Side-by-Side Annual Cost

Annual Volume AssemblyAI Deepgram (Growth) Difference
1,200 hrs (100/mo) $204 $696 AssemblyAI saves $492
6,000 hrs (500/mo) $1,020 $3,060 AssemblyAI saves $2,040
12,000 hrs (1,000/mo) $2,040 $6,120 AssemblyAI saves $4,080
120,000 hrs (10,000/mo) $20,400 $61,200 AssemblyAI saves $40,800

At high volume, AssemblyAI's lower per-hour rate creates significant annual savings. Both providers offer additional enterprise discounts at very high volumes — contact their sales teams for custom quotes.

Free Tier Comparison

Deepgram offers $200 in credits (~435 hours at Nova-3 rates) compared to AssemblyAI's 185 hours of pre-recorded transcription — Deepgram's free tier provides more evaluation capacity. BrassTranscripts requires no free tier because there's no account or API setup — just upload a file and pay per transcript.

Both APIs offer generous free tiers for evaluation and small projects.

Feature AssemblyAI Deepgram
Free credit 185 hours pre-recorded $200 credit (~435 hrs at Nova-3)
Credit card required No No
Streaming included 333 hours Yes (same credit pool)
Expiration Not published Not published

Deepgram's $200 credit translates to more free hours because it covers all API usage from a single credit pool. AssemblyAI's free tier is measured in hours directly.

Feature Matrix: What Each API Offers

AssemblyAI offers more audio intelligence features (summarization, sentiment analysis, entity detection) while Deepgram provides self-hosted deployment and faster real-time streaming — the right choice depends on technical requirements, not just price.

Beyond pricing, the two APIs serve different needs.

Feature AssemblyAI Deepgram
Pre-recorded transcription Yes Yes
Real-time streaming Yes Yes
Speaker diarization Yes (add-on) Yes (add-on)
Language support 30+ languages 36+ languages
Summarization Yes (add-on) No
Sentiment analysis Yes (add-on) No
Entity detection Yes (add-on) No
Topic detection Yes (add-on) No
PII redaction Yes (add-on) Yes (add-on)
Custom vocabulary Yes Yes
Webhook callbacks Yes Yes
Self-hosted option No Yes (on-prem)
HIPAA compliance Yes (BAA available) Yes (BAA available)
Per-second billing Yes Yes

AssemblyAI strength: Audio intelligence features (summarization, sentiment, entity detection) built into the same API call. Better for teams that need post-processing without a separate LLM pipeline.

Deepgram strength: Faster real-time streaming, self-hosted deployment option, and broader language model selection. Better for latency-sensitive applications and on-premises requirements.

Volume Discounts and Enterprise Pricing

Deepgram publishes structured volume discounts through their Growth plan (up to 20% savings), while AssemblyAI requires contacting sales for custom enterprise pricing at high volumes.

AssemblyAI Volume Discounts

AssemblyAI doesn't publish volume discount tiers. Their pricing page states: "If you plan to send large volumes of audio and video content through our API, please reach out to us to see if you qualify for a volume discount."

For high-volume pricing, contact AssemblyAI sales.

Deepgram Volume Discounts

Deepgram offers structured discounts through their Growth plan:

  • Growth plan: $4,000+/year pre-paid, up to 20% savings on published rates
  • Enterprise: Custom pricing for very high volumes

Deepgram also offers refunds for unused credits within 30 days — useful for testing at scale before committing.

When to Skip the API Entirely

BrassTranscripts offers flat-rate transcription with speaker identification included and no API integration required — for teams that need transcription without writing code, a web-based service eliminates development overhead entirely.

Both AssemblyAI and Deepgram are developer APIs. They require:

  • Writing code to integrate with your application
  • Managing API keys, authentication, and error handling
  • Building a UI for uploading and viewing transcripts
  • Handling webhook callbacks for async processing
  • Maintaining your integration as APIs change

If you don't need an API — you just need audio files transcribed — a web-based service eliminates the development overhead entirely.

BrassTranscripts offers flat-rate transcription with a simple upload interface:

Feature BrassTranscripts AssemblyAI Deepgram
Web upload Yes No (API only) No (API only)
Speaker ID included Yes +$0.02/hr +$0.12/hr
Coding required No Yes Yes
Pricing model Flat rate per file Per minute + add-ons Per minute + add-ons
1-15 min file $2.50 ~$0.04-0.07 ~$0.09-0.15
60 min file $6.00 ~$0.17 ~$0.58
120 min file $6.00 ~$0.34 ~$1.16

For individual files and small batches, BrassTranscripts' flat rate is more predictable — no calculating minutes, no add-on fees, no API integration. For files over 30 minutes, the flat $6.00 rate is often cheaper than per-minute pricing.

Processing audio files in bulk? Our bulk transcription service handles 20+ files in a single batch at $2.50/file with volume pricing, speaker identification included. No API required — just upload and download.

Upload your audio file →

Conclusion

For high-volume API transcription, AssemblyAI costs less per hour than Deepgram at every published pricing tier — roughly 3x cheaper at base rates, and still significantly cheaper after adding speaker identification. The gap widens at scale: processing 10,000 hours monthly costs $1,700/month with AssemblyAI vs $5,100/month with Deepgram.

However, Deepgram offers advantages in streaming latency, self-hosted deployment, and a more generous free tier. Choose based on your technical requirements, not just price.

For teams that don't need API integration — just accurate transcription with speaker identification — BrassTranscripts provides flat-rate pricing with no development overhead.


Pricing sources:

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AssemblyAI vs Deepgram: API Pricing for High Volume