# Amazon Polly vs eSpeak NG

**Leader by vioscaleAI score:** Amazon Polly

| Attribute | Amazon Polly | eSpeak NG |
|---|---|---|
| **vioscaleAI score** | 74.2 (73% (medium)) | 41.5 (38% (low)) |
| activity.commits_last_30d | - | 42 |
| adoption.dependent_repos | - | 0 |
| adoption.github_stars | - | 6,945 |
| content.faq | `[{"answer":"Amazon Polly is a managed cloud service that synthesizes speech from text using neural networks and generative voice technology. It offers multiple voice options and languages, integrates through APIs, and supports various audio formats for use in applications and services. It is indexed under Text To Speech.","source":"https://aws.amazon.com/polly/pricing/","question":"What is Amazon Polly?","confidence":0.6},{"answer":"Amazon Polly offers a free tier, so you can start without paying. Paid plans start at $4. Prices are published openly on the vendor's own pricing page. Pricing changes often, so verify at source before relying on it.","source":"https://aws.amazon.com/polly/pricing/","question":"Is Amazon Polly free?","confidence":0.6},{"answer":"Amazon Polly supports the web and a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://aws.amazon.com/polly/pricing/","question":"What platforms does Amazon Polly support?","confidence":0.6},{"answer":"We have only confirmed a cloud / SaaS deployment for Amazon Polly, so it appears to be vendor-hosted. If a self-hosted option exists we have not found it documented publicly.","source":"https://aws.amazon.com/polly/pricing/","question":"Can Amazon Polly be self-hosted?","confidence":0.6},{"answer":"We have confirmed 4 integrations for Amazon Polly, including Amazon Connect, Amazon Chime SDK, AWS Chime SDK and Alexa Skills. This is what we could verify from public sources, so the vendor may support others we have not indexed.","source":"https://aws.amazon.com/polly/pricing/","question":"What does Amazon Polly integrate with?","confidence":0.6},{"answer":"We have independently confirmed SOC 2, ISO 27001, HIPAA and GDPR for Amazon Polly. Certifications we do not list are ones we have not been able to verify from public sources, which is not the same as Amazon Polly not holding them. Always confirm compliance directly before you rely on it.","source":"https://aws.amazon.com/trust-center/?nc1=f_cc","question":"What security certifications does Amazon Polly have?","confidence":0.7},{"answer":"Amazon Polly is available worldwide. The vendor is headquartered in the United States.","source":"https://aws.amazon.com/polly/pricing/","question":"Where is Amazon Polly available?","confidence":0.75}]` | `[{"answer":"A lightweight open source text-to-speech engine that converts written text into spoken audio using formant synthesis. Available as a command-line tool and C/library for integration across Linux, Windows, Android, and other platforms. It is indexed under Text To Speech.","source":"https://github.com/pricing","question":"What is eSpeak NG?","confidence":0.6},{"answer":"eSpeak NG is open source, so it can be self-hosted and used at no licence cost. It is released under the GPL-3.0 licence. Pricing changes often, so verify at source before relying on it.","source":"https://github.com/pricing","question":"Is eSpeak NG free to use?","confidence":0.6},{"answer":"eSpeak NG supports Windows, macOS, Linux, Android and a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://github.com/pricing","question":"What platforms does eSpeak NG support?","confidence":0.6},{"answer":"Yes. eSpeak NG can be deployed self-hosted, so it does not have to run on the vendor's infrastructure.","source":"https://github.com/pricing","question":"Can eSpeak NG be self-hosted?","confidence":0.6},{"answer":"We have confirmed 3 integrations for eSpeak NG, including MBROLA, SAPI5 and C API library integration. This is what we could verify from public sources, so the vendor may support others we have not indexed.","source":"https://github.com/pricing","question":"What does eSpeak NG integrate with?","confidence":0.6},{"answer":"Yes. eSpeak NG is published under the GPL-3.0 licence, a copyleft licence, so check its terms before embedding it in a closed-source product. Licence terms can change between releases, so verify against the repository for the version you intend to use.","source":"https://github.com/espeak-ng/espeak-ng","question":"Is eSpeak NG open source?","confidence":0.95}]` |
| deployment.options | `{"cloud":true}` | `{"on_prem":true,"self_hosted":true}` |
| description.long | A cloud-based text-to-speech service that transforms written text into spoken audio using neural AI models. Supports multiple languages and voices with customization through markup language tags and pronunciation rules. | An open source application that generates audio speech from text, supporting numerous languages across Windows, Linux, and Android systems. It employs sound-generation technology to produce clear but synthesized speech efficiently on computers and mobile devices. |
| features.capabilities | `{"open_source":false,"ssml_support":true,"pricing_model":"pay_per_character_api","on_device_offline":false,"architecture_model":"managed_cloud_saas_and_api","streaming_synthesis":true,"phoneme_level_pronunciation_dictionary_overrides":true}` | `{"open_source":true,"ssml_support":true,"on_device_offline":true}` |
| integrations.count | 3 | 3 |
| integrations.list | `[{"name":"Amazon Connect"},{"name":"Amazon Chime SDK"},{"name":"AWS Chime SDK","native":true,"category":"communications","direction":"bidirectional"},{"name":"Alexa Skills","native":true,"category":"voice_assistant","direction":"bidirectional"},{"name":"Amazon Chime","native":true,"category":"chat"}]` | `[{"name":"MBROLA"},{"name":"SAPI5"},{"name":"C API library integration"}]` |
| language.primary | - | C |
| license.spdx | - | GPL-3.0 |
| market.availability | `{"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` | - |
| platform.support | `{"cli":true,"web":true}` | `{"cli":true,"linux":true,"android":true,"windows":true}` |
| pricing | `{"type":"usage","plans":[{"free":true,"name":"Standard Voices","summary":"$4.00 per 1M characters. 5M free/month.","features":["Standard text-to-speech voices","SSML support","Custom pronunciation lexicons"],"components":[{"per":{"qty":1000000,"unit":"characters"},"kind":"metered","amount":4,"currency":"USD"}],"contactSales":false,"includedLimits":{"free_tier":"5M characters/month"}},{"free":true,"name":"Neural Voices","summary":"$16.00 per 1M characters. 1M free/month (first year).","features":["High-quality neural voices","Newscaster speaking style","SSML support","Speech Marks metadata"],"components":[{"per":{"qty":1000000,"unit":"characters"},"kind":"metered","amount":16,"currency":"USD"}],"contactSales":false,"includedLimits":{"free_tier":"1M characters/month (first 12 months)"}},{"free":true,"name":"Long-Form Voices","summary":"$100.00 per 1M characters. 500k free/month (first year).","features":["Long-form optimized voices","Extended synthesis support","SSML support"],"components":[{"per":{"qty":1000000,"unit":"characters"},"kind":"metered","amount":100,"currency":"USD"}],"contactSales":false,"includedLimits":{"free_tier":"500k characters/month (first 12 months)"}},{"free":true,"name":"Generative Voices","summary":"$30.00 per 1M characters. 100k free/month (first year).","features":["Generative voice synthesis","Advanced voice quality","Bidirectional streaming API"],"components":[{"per":{"qty":1000000,"unit":"characters"},"kind":"metered","amount":30,"currency":"USD"}],"contactSales":false,"includedLimits":{"free_tier":"100k characters/month (first 12 months)"}}],"summary":"From $4.00 per 1M characters (Standard Voices). Four voice type tiers with different pricing. Free tier includes millions of monthly characters depending on voice type.","currency":"USD","freeTier":true,"sourceUrl":"https://aws.amazon.com/polly/pricing/","retrievedAt":"2026-09-29T10:45:58.659Z","billingPeriods":["month"]}` | `{"type":"open_source","freeTier":true,"sourceUrl":"https://github.com/pricing","retrievedAt":"2026-10-14T22:37:23.101Z"}` |
| pricing.free_tier | yes | yes |
| pricing.model | freemium | open_source |
| pricing.price_level | low | free |
| pricing.starting_price | `{"amount":4,"currency":"USD"}` | - |
| pricing.transparent | yes | yes |
| release.cadence_days | - | 799 |
| release.history | - | `[{"url":"https://github.com/espeak-ng/espeak-ng/releases/tag/1.52.0","date":"2024-12-12T13:47:27Z","type":"stable","version":"1.52.0"},{"url":"https://github.com/espeak-ng/espeak-ng/releases/tag/1.51","date":"2022-04-02T19:43:39Z","type":"stable","version":"1.51"},{"url":"https://github.com/espeak-ng/espeak-ng/releases/tag/1.50","date":"2019-12-02T12:34:16Z","type":"stable","version":"1.50"},{"url":"https://github.com/espeak-ng/espeak-ng/releases/tag/1.49.2","date":"2017-09-24T09:37:08Z","type":"stable","version":"1.49.2"},{"url":"https://github.com/espeak-ng/espeak-ng/releases/tag/1.49.1","date":"2017-01-21T21:20:08Z","type":"stable","version":"1.49.1"},{"url":"https://github.com/espeak-ng/espeak-ng/releases/tag/1.49.0","date":"2016-09-10T10:20:46Z","type":"stable","version":"1.49.0"}]` |
| reliability.status_page | yes | - |
| security.certifications | `[{"name":"PCI DSS","status":"active"},{"name":"HIPAA/HITECH","status":"active"},{"name":"FedRAMP","status":"active"},{"name":"FIPS 140-3","status":"active"},{"name":"NIST 800-171","status":"active"}]` | - |
| security.disclosure_policy | yes | - |
| security.fedramp | yes | - |
| security.gdpr | yes | - |
| security.hipaa | yes | - |
| security.iso27001 | yes | - |
| security.pci | yes | - |
| security.scorecard | - | 4.7 |
| security.soc2 | yes | - |
| security.trust_center | https://aws.amazon.com/compliance/ | https://github.com/security |
| security.vulnerabilities | - | `{"count":0,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=debian&package_name=espeak-ng&per_page=100","last_12m":0,"max_severity":null}` |

## Capabilities (Text To Speech)

| Capability | Amazon Polly | eSpeak NG |
|---|:--:|:--:|
| **Capabilities** |  |  |
| Voice cloning | - | - |
| Zero shot cloning | - | - |
| Streaming synthesis | ✓ | - |
| Ssml support | ✓ | ✓ |
| Emotion style control | - | - |
| On device offline | ✗ | ✓ |
| Open source | ✗ | ✓ |
| Watermarking provenance | - | - |
| Cloning consent verification | - | - |

*Source: vioscaleAI. Generated 2026-10-16T20:01:31.018Z. "-" = undocumented, not absent.*