iSpeech vs Yandex SpeechKit

iSpeech provides text-to-speech and automated speech recognition through APIs, SDKs, and online tools. Its speech API can synthesize audio with multiple voices, formats, bitrates, frequencies, and playback speeds, and supports MathML and SSML. The API can also transcribe submitted audio across multiple languages and recognition models; iSpeech says custom models can be created. The homepage lists support for more than 30 languages. Audio downloads are available in AIFF, MP3, OGG, WMA, FLAC, WAV, A-law, μ-law, VOX, and MP4 formats. Listed access includes Android, iOS, Linux, macOS, web, Windows, API, and extension. The Basic plan is free for personal use, and commercial use is listed as available. Plus costs $2.95 a month, billed monthly, and includes 30-minute recordings, approximately 4,167 words. Premium costs $3.95 a month, billed monthly, with 12-hour recordings, approximately 100,000 words. Pay Per Use costs $50 a month for dynamic TTS usage only and includes 2,000 credits. Pay Per Install costs $0.25 a month and has a 10,000-install minimum.

Yandex SpeechKit is a managed speech-synthesis service available through a web interface and API. It supports voice cloning, six languages, and audio output in LPCM, OggOpus and MP3. Input is limited to 250 characters. Speech synthesis API v3 plans for Kazakhstan and Russia each list 250 characters and 24 seconds, while Brand Voice Self Service and Brand Voice Premium provide custom unique voice synthesis with request-based pricing; no prices are listed for these plans. A free plan is available, although the pricing model is marked paid. The entry lists two cloud regions and a 2018 founding date, with headquarters in Dubai. Related managed infrastructure includes encrypted persistent storage, snapshots, high availability, private networking and seven-day backup retention. Storage volumes can reach 256 TB, with several volume types. Managed clusters support Valkey and Redis, and S3 compatibility is listed.