TL;DR: Azure Speech Services and Gladia both meet enterprise compliance requirements, including SOC 2 Type 2, GDPR, and EU data residency, so the "Microsoft is the safe bet" argument doesn't hold the weight it once did. Where they diverge is cost structure and integration velocity. Azure's real-time transcription with diarization runs $1.50/hour and compounds with ecosystem lock-in costs, while our Pro plan covers all features at $0.612/hour. For product teams building multilingual voice applications at Series A to C scale, our all-inclusive pricing and sub-24-hour integration window remove two of the most common blockers in vendor decisions.
For product leaders making foundational infrastructure decisions, the choice between Azure Speech Services and Gladia surfaces a tension that goes beyond feature lists. Azure represents the gravitational pull of the hyperscaler ecosystem, where compliance feels pre-approved and procurement conversations are familiar. We represent a different bet: a speech-specialized API that matches Azure on the compliance requirements your legal team will check, while offering pricing predictability and integration speed that Azure's architecture structurally cannot.
This guide compares both platforms on the metrics that drive roadmap decisions at Series A to C companies: SLA guarantees, data residency configuration, pricing at realistic volume, multilingual accuracy, and time to production.
Executive summary: The strategic trade-off between Azure and Gladia
The core question isn't which vendor has better marketing. It's whether Azure's ecosystem depth justifies the complexity and cost overhead it introduces for a team whose core product isn't Microsoft infrastructure.
| Dimension |
Azure Speech Services |
Gladia |
| SLA uptime | 99.9% (paid tiers) | Available in enterprise contracts |
| SOC 2 Type 2 | Yes | Yes |
| GDPR / EU data residency | Yes, region-configurable | Yes, EU by default (France) |
| HIPAA | Yes | Yes |
| Pricing model | Per-feature metering | All-inclusive per-second billing |
| Real-time + diarization rate | ~$1.30/hour (flagged) | $0.612/hour (Pro) |
| Default training data use | Explicit customer consent required | Never on paid plans |
| Diarization included | Add-on for real-time | Included at base rate |
| Setup time | Multi-step SDK + portal | API key, REST or WebSocket |
| Languages supported | ~100 | 110+ |
Azure's 99.9% uptime SLA is backed by Microsoft's financial weight and mature incident infrastructure. Uptime terms are defined within enterprise contracts rather than on a public SLA page; enterprise customers typically see 99.9% or higher terms depending on volume tier, and these are available for review during security evaluation. Both platforms carry the compliance certifications that enterprise procurement requires, but how they get you there differs significantly in cost and operational overhead, as our security documentation and the Azure Trust Center each lay out.
Compliance and data residency: Comparing enterprise readiness
The "Microsoft is safer" assumption doesn't survive contact with the actual compliance documentation for either platform. Both Azure and Gladia are SOC 2 Type 2 certified, both offer GDPR-aligned EU data residency, and both publish DPAs that a legal team can review before signature.
Azure's regional availability and data processing agreements
Azure's approach to EU data residency is comprehensive but requires deliberate configuration. The EU Data Boundary program covers in-scope services when deployed to EU regions, but guaranteeing strict EU-only processing requires deploying specifically to Germany West Central or Sweden Central Data Zone regions. West Europe or France Central alone don't provide the same guarantee under Microsoft's current terms.
Azure conducts SOC 2 Type 2 audits on a rolling 12-month window with reports issued semi-annually, which satisfies most enterprise audit requirements. The compliance posture is sound, but configuring it correctly for a specific EU data residency requirement takes engineering time and ongoing attention as region configurations change.
Gladia's GDPR compliance and zero-retention default
Our compliance stack covers the same audit standards without the configuration complexity. We are SOC 2 Type 2 certified and HIPAA-compliant, maintaining a BAA for covered entities, and are also ISO 27001 compliant. EU data residency is on by default, using a European provider based in France, with other geographies and specific hosting providers available on request per our security page.
The data training policy is where Azure Speech Services and Gladia diverge most sharply in practice. Azure's real-time Speech Services, specifically the Speech Services layer, not the broader Azure AI stack, processes audio in server memory without storing it at rest, as Azure's data privacy documentation confirms. Microsoft does not use customer data to improve its Speech models or for any other purpose without explicit customer consent, per Microsoft's published documentation.
We take the same default position on training data, with additional clarity across all plan tiers. Audio on our Pro and Enterprise plans is never used to retrain our models, and no opt-out clause is required. Custom data retention policies are available, including 1-month, 1-week, 1-day, and zero-retention options, via our data retention documentation. Free plan users should be aware that their data can be used for model training, which is standard practice across the industry for free tiers.
"It's based in EU so it fits our GDPR compliance requirements... The team is very reactive and helpful... as per our experience, they've had great reliability." - Robin L. on G2
SLA guarantees and reliability benchmarks
Azure's 99.9% SLA for paid cognitive services permits roughly 8.7 hours of downtime per year, with no contractual requirement that the allowance be spread evenly across the calendar. A single incident could consume the full 8.7 hours, meaning your production pipeline is down for the better part of a day within the terms of a compliant SLA. Microsoft backs the guarantee with service credits rather than refunds for the full business impact of downtime, which is worth modeling separately from the headline percentage.
We provide specific SLA terms and uptime percentages in enterprise contracts rather than a public SLA page; typical enterprise agreements target 99.9% availability or higher, with specific terms available for review before signature. During vendor evaluation, request this documentation explicitly, along with incident history and the current status page. Mature incident documentation signals operational discipline, not weakness, and it's a fair request at any volume tier.
The practical reliability question for most product teams is whether the platform has had incidents during their evaluation period and how those incidents were handled. Our direct engineering support, accessible through Slack for active customers, means escalations reach technical staff rather than a support ticket queue.
Multilingual accuracy: Testing WER on real-world audio
Accuracy benchmarks on curated studio audio tell you almost nothing about what will happen in production. What matters is WER on noisy, accented, multilingual audio that reflects your actual user base, tested on datasets like Mozilla Common Voice or Google FLEURS rather than vendor-controlled test sets. You can review our published benchmark methodology and dataset references at gladia.io/competitors/benchmarks.
Word Error Rate (WER) measures the percentage of words a model transcribes incorrectly. A 10% WER means one in ten words is wrong, which compounds quickly in downstream tasks like summarization or named entity recognition. Code-switching refers to mid-conversation language changes within a single audio file, a common pattern in bilingual customer support and consumer voice products serving diverse markets.
Azure's language identification lets you supply candidate languages (up to 4 for at-start LID, up to 10 for continuous LID) and the service returns the detected language from those candidates, as Azure's LID documentation describes. This configuration requires a separate setup step and is not active by default for basic speech-to-text requests.
We include automatic language detection and switching in the base offering, with support for 100+ languages and dialects across both real-time and async modes without additional configuration. Our audio intelligence documentation covers how these features work across both pipeline types, which matters when your audio includes bilingual speakers or regional dialects.
"We have tested it across many many languages (we work with commentators in pro sports around the world) and have found great accuracy even with custom fields such as team names, player names, etc. We have never come across any sort of hallucination." - Xavier G. on G2
"Gladia deliver real time highly accurate transcription with minimal latency, even across multiple languages and accents." - Faes W. on G2
Cost predictability: Azure's pay-as-you-go vs. Gladia's flat rate
This is where the strategic decision becomes a unit economics decision. Azure's pricing structure separates every capability into its own meter, and the costs compound in ways that are genuinely difficult to model before your first production month.
Azure's pricing structure (per Azure's pricing announcement):
Standard real-time transcription: $1.00/hour
Speaker diarization add-on (real-time): $0.30/hour
Batch transcription: $0.36/hour (diarization included)
Custom Speech model training: $10.00 per compute hour
Custom model hosting: $0.0538 per model per hour
As Naitive Cloud's enterprise STT analysis notes, building a production transcription pipeline on Azure isn't just about Speech Services pricing, it's about the compounding effect of each unbundled service metered separately.
Our Pro plan runs $0.612/hour and includes speaker diarization, automatic language detection, 100+ language support, GDPR and SOC 2 Type 2 compliance, with no setup fees and no add-on charges for standard audio intelligence features.
| Volume (hours/month) |
Azure Real-Time + Diarization |
Azure Batch + Diarization |
Gladia Pro |
| 1,000 hours |
$1,300 |
$360 |
$612 |
| 10,000 hours |
$13,000 |
$3,600 |
$6,120 |
| 50,000 hours |
$65,000 |
$18,000 |
$30,600 |
Azure offers commitment-based discounts at high annual volume, with the standard transcription rate dropping to $0.50/hour at 50,000 committed hours annually. Those discounts require upfront volume commitments that introduce their own planning risk for teams whose usage is still growing.
"Gladia provides a highly accurate real-time speech-to-text solution for high volumes of support and service calls. Latency is low and accuracy high, even for numericals. We've appreciated the quality of support across pre-processing, post-processing, and model optimization." - Verified user on G2
Integration velocity: Time-to-production comparison
The integration experience between Azure and Gladia reflects the broader difference between a hyperscaler platform and a specialized API.
Azure's integration path requires creating an Azure account, provisioning a Cognitive Services resource in the correct region, obtaining a subscription key and region-specific endpoint, and installing the Speech SDK or configuring REST/WebSocket authentication. For basic Speech Services access, a subscription key and region are sufficient; Azure AD (Microsoft Entra ID) authentication with managed identity is an optional alternative needed only when integrating with other Azure services that specifically require it. Each feature, including diarization and language identification, requires separate pipeline configuration.
Our integration path requires two steps: sign up at gladia.io, get an API key from the dashboard, then make a REST or WebSocket API call with the key in the header. As one developer noted after working through our integration process: Setting up the API took less than a day, and the integration process was smooth, supported by detailed documentation and responsive support.
"API is simple to get up and running. The team is supportive on slack." - Ankur D. on G2
"In less than a day of dev work we were able to release a state-of-the-art speech-to-text engine!" - Xavier G. on G2
Teams already using other STT providers can reference our migration guides for switching from AssemblyAI or switching from Deepgram to compress migration timeline estimates. Our no-code playground walkthrough shows the full integration flow and lets you test accuracy on real audio without writing a single line of code, compressing a proof-of-concept from weeks to hours.
Recommendation: Which infrastructure fits your stage?
The decision breaks along a clear axis: ecosystem integration requirements versus product development velocity.
Choose Azure Speech Services if:
Your organization has existing committed Azure spend and the marginal cost of adding Speech Services is covered by that commitment
Your product requires deep integration with other Azure services like Azure OpenAI, Azure Bot Service, or Microsoft 365
Your security team requires all vendor relationships to route through the Microsoft procurement and contract framework
You have dedicated DevOps capacity to manage Azure resource configuration and region deployment
Choose Gladia if:
You need a production-ready integration within days rather than weeks
Your cost model needs to hold up with diarization and audio intelligence included at base volume
Your product serves a multilingual user base where code-switching and accented audio are production realities
Our legal team's compliance checklist includes SOC 2 Type 2, GDPR, ISO 27001, and EU data residency, and you need documentation before contract signature.
You want direct engineering support rather than tiered support tickets
For most product teams at Series A to C building global voice applications, we remove three evaluation risks simultaneously: the pricing uncertainty from feature-metered billing at scale, the configuration overhead of Azure's regional compliance setup, and the integration quarter that delays everything else on the roadmap.
Our buyer's guide walks through the full vendor evaluation framework, including the questions worth asking any STT provider before committing. You can also review outcomes from teams in AI healthcare transcription and AI sales analytics workflows to see the API applied across production use cases.
Get started with 10 free hours and have your integration in production in less than a day or book a demo with the team for a walkthrough of volume pricing and compliance documentation specific to your architecture.
Frequently asked questions
How does Gladia handle on-premises or air-gapped deployment requirements?
We support cloud-hosted and custom enterprise hosting, with flexible geographic deployment across US and EU clusters to meet your security requirements. Enterprise configurations are scoped individually, where we work through your specific latency, compliance, and SLA needs before finalizing terms.
Does Azure use customer audio to train its speech models by default?
Azure processes real-time speech audio in server memory without storage at rest—this applies specifically to the Speech Services layer, not to other Azure AI services that may have separate data handling terms—and Microsoft does not use customer data to improve its Speech models or for any other purpose without explicit customer consent, per Microsoft's published documentation. Gladia does not use audio from paid plans at any tier for model training, and no opt-out is required.
Azure guarantees 99.9% availability for paid Cognitive Services tiers, backed by service credits, with no SLA for the free tier. That 99.9% figure equates to roughly 8.7 hours of allowable downtime per year, which could occur as a single incident rather than distributed across the calendar.
How many languages does Gladia support vs. Azure?
Gladia supports 100+ languages and dialects, with automatic code-switching included in the base rate. Azure supports approximately 100 languages and requires additional configuration steps to enable mid-conversation language switching.
What does Azure's diarization add-on cost for real-time transcription?
Azure charges $0.30/hour for the speaker diarization add-on on real-time transcription, on top of the $1.00/hour base rate, per Azure's published pricing. Gladia includes speaker diarization at the base Pro plan rate of $0.612/hour.
Can I switch from Azure Speech Services to Gladia without a full re-architecture?
Our REST and WebSocket API structure requires only an API key swap for most pipeline configurations. Reference our migration documentation for step-by-step guidance.
Key terminology
Word Error Rate (WER): The percentage of words transcribed incorrectly, calculated as the sum of substitutions, deletions, and insertions divided by total words in the reference transcript. Lower is better, and a 5% WER means 1 in 20 words is wrong.
Diarization: The process of segmenting an audio recording by speaker identity, answering "who spoke when" rather than just "what was said." Useful for call center recordings, meetings, and interview transcription.
Code-switching: The phenomenon of speakers alternating between two or more languages within a single conversation or audio file. Common in bilingual markets and multinational support calls.
Data residency: The requirement that data be stored and processed within a specific geographic jurisdiction, typically driven by GDPR for EU-based organizations or sector-specific regulations like HIPAA in healthcare.
SOC 2 Type 2: A third-party audit certification that verifies a service organization's security controls operated effectively over a defined review period, typically 6 to 12 months. Type 2 is more rigorous than Type 1, which only verifies that controls exist.
Zero-retention processing: A data handling posture in which audio and transcription output are processed in memory and not persisted to storage after the request completes, with no logging retained for model improvement.
Total Cost of Ownership (TCO): The full cost of a vendor relationship at a given usage volume, including base transcription fees, feature add-on charges, support plan costs, and engineering time required for integration and maintenance.
Latency budget: The total allowable time from audio input to a useful output in a real-time pipeline. In voice agent pipelines, transcription latency compounds with LLM response time, so each millisecond saved at the STT layer directly improves end-user perceived responsiveness.