Introduction
I've evaluated every free tier in the speech-to-text market — and here's what nobody tells you: most of them aren't actually free. One provider's "free tier" costs you $200 in surprise bills the moment you cross an invisible line. Another's expires in 12 months with no warning.
In this guide, I'll break down exactly what each major speech-to-text API gives you for $0, where the hidden traps are, and which free tier is genuinely useful for production testing. If you're comparing options, our pricing page shows how our fixed-rate plans compare once you outgrow the free tier.
What "Free Tier" Really Means
"Free tier" is a marketing term with three distinct meanings in speech-to-text. I've seen teams confuse them and get burned:
- True free tier — ongoing allowance with no expiration. Rare.
- Free credit — one-time trial budget. Most common.
- Time-limited trial — free for X months, then paid-only. Common with cloud providers.
The difference matters. A $200 credit covers one batch job on a 500-hour dataset — then it's gone. A true free tier of 3 hours per month is less exciting, but it's renewable forever — what you actually need for iterative development.
Provider-by-Provider Breakdown
| Provider | Free Offering | Real Value | Expires? |
|---|---|---|---|
| Privocio | 3 hrs / 4 weeks | ~12 hrs/month | No |
| Deepgram | $200 credit | ~775 hours | One-time |
| AssemblyAI | $50 credit | ~135 hours | One-time |
| Google Cloud STT | 60 min/month | 1 hour/month | No |
| AWS Transcribe | 60 min/month | 1 hour/month | After 12 months |
| Azure Speech | 5 hrs/month | 5 hours/month | After 12 months |
| Rev AI | $20 credit | ~16 hours | One-time |
| OpenAI Whisper API | None | $0 | N/A |
Privocio — 3 Hours per 4 Weeks
Our free tier gives you 3 hours every 4 weeks — roughly 12 hours per month. No credit card required. No expiration. You can test the full API including our Agent output mode and self-hosted deployment without time pressure.
I recommend this for teams doing a 2-3 week evaluation. It's enough to process a real dataset, test webhook integration, and measure token savings on your actual LLM pipeline.
Deepgram — $200 One-Time Credit
Deepgram offers $200 in credits. At their Nova-2 pricing, that's roughly 775 hours. It's enormous for a one-off project, but it's a credit, not a tier. I burned through $180 in a single week testing real-time streaming on a 50-hour dataset.
AssemblyAI — $50 One-Time Credit
AssemblyAI gives you $50 to start — about 135 hours. Their free tier shines if you want to test audio intelligence features like sentiment analysis and PII redaction, but it's a one-time pool.
Google Cloud Speech-to-Text — 60 Minutes per Month
Google Cloud offers 60 minutes free per month. This is a true recurring free tier — it never expires. But 60 minutes is barely enough for a small test. I typically burn through this in the first afternoon of integration testing.
AWS Transcribe — 60 Minutes per Month (12 Months)
AWS Transcribe gives you 60 minutes per month for your first 12 months. After that, the free tier vanishes entirely. I've seen teams build prototypes around AWS Transcribe only to discover their bill jumps from $0 to $400/month when the trial expires.
Azure Speech — 5 Hours per Month (12 Months)
Azure Speech offers 5 hours free per month for the first 12 months. This is the most generous time-limited trial. The catch is the 12-month cliff — after that, you're paying standard rates with no free buffer.
Rev AI — $20 One-Time Credit
Rev AI gives you $20 to start. At ~$0.02/minute, that's about 16 hours. It's enough to test their accuracy against your audio, but not much more.
OpenAI Whisper API — No Free Tier
OpenAI Whisper API has no free tier. You pay from the first minute at $0.006/minute. If you want a free option, you need to self-host open-source Whisper on your own hardware.
The Hidden Traps in Free Tiers
I've watched three teams get caught by free tier traps in the past year:
- Credit card requirement: Most providers require a card "for verification." One accidental batch job and you're billed.
- Silent expiration: AWS and Azure free tiers expire after 12 months with no warning. Your bill goes from $0 to hundreds overnight.
- Rounding games: Per-minute billing often rounds up to the nearest 15 seconds. At scale, this adds 20-30% to your effective cost.
Which Free Tier Should You Choose?
| Use Case | Best Free Option | Why |
|---|---|---|
| Quick API integration test | Privocio or Google Cloud | No credit card, no expiration |
| Large one-time dataset | Deepgram ($200 credit) | Most raw hours for free |
| Audio intelligence testing | AssemblyAI ($50 credit) | Sentiment, PII, LeMUR included |
| Microsoft ecosystem integration | Azure Speech (5 hrs/month) | Best trial for Azure-native teams |
| Long-term prototyping | Privocio (3 hrs/4 weeks) | Never expires, full feature access |
Bottom line: If you need a free tier for ongoing development, Privocio's renewable 3 hours per 4 weeks or Google Cloud's 60 minutes per month are your only true no-strings options. Everyone else is giving you a timed trial dressed up as a free tier.
Frequently Asked Questions
Which speech-to-text API has the most generous free tier?
Deepgram's $200 credit gives you the most raw hours (~775), but it's one-time. For ongoing development, Azure Speech's 5 hours per month for 12 months is the most generous time-limited option. For truly free forever, Privocio's 3 hours per 4 weeks and Google Cloud's 60 minutes per month are the only non-expiring options.
Do I need a credit card for speech-to-text API free tiers?
Most providers require a credit card even for the free tier. Deepgram, AssemblyAI, Google Cloud, AWS, and Azure all require billing details. Privocio is the exception — our free tier doesn't require a credit card.
What happens when my free tier expires?
AWS Transcribe and Azure Speech free tiers expire after 12 months and convert to full pay-per-use pricing. Deepgram and AssemblyAI credits are one-time — once spent, you start paying immediately. Only Google Cloud and Privocio offer non-expiring free tiers.
Is self-hosted Whisper really free?
The open-source Whisper model is free to download, but it's not free to operate. You need GPU hardware, ongoing maintenance, and engineering time. I've seen teams spend $300/month in cloud GPU costs trying to "save money" with self-hosted Whisper. For most teams, a managed API is cheaper at any realistic scale.
Conclusion: Pick the Free Tier That Matches Your Timeline
Free tiers aren't all the same. If you're running a one-week evaluation on a 100-hour dataset, Deepgram's $200 credit is unbeatable. If you're building a product that needs 6 months of iteration, you need a renewable free tier — your options narrow to Privocio, Google Cloud, or eventually paying.
I've found that most teams overestimate how much free audio they need. Three hours of well-chosen test audio tells you more about an API than 200 hours of random files. Start with a focused test, measure accuracy on your actual audio, and then decide whether fixed pricing or per-minute billing makes sense.
If you want to test Privocio's free tier — no credit card, no expiration — start transcribing immediately on our free plan. For the full pricing comparison, read our complete guide to speech-to-text API pricing.
Image Credits:
Cover image sourced from Unsplash (Unsplash License).