Text-to-speech price per million characters: 11 rates vs Sume

Sume TTS 1.0 costs $47.50 per million characters, which puts it eighth of the eleven rates below: more expensive than Rime Mist v3 at $30 and Deepgram Aura-2 at $30, and slightly cheaper than Rime Coda at $50. All figures come from the vendor pages read on 2026-10-05 and are converted to dollars per million characters so they line up. Voice quality, latency and language coverage are not in the price.

The ranking

Per-1K rates are multiplied by 1,000 to get a per-million figure. Where two vendors list the same rate for the same model name, the table shows them on one row. Hume's per-character rates are listed per plan, so the rows show the lowest and highest.

Read these before quoting

Speechmatics lists its first 1M characters as free, so the first million costs nothing there. Microsoft's two MAI-Voice rates are from the launch announcement and are stated per million characters. Hume's rates depend on plan, and its cheapest per-character figures come from larger monthly plans, so a small user pays the top of the range.

Soniox's TTS is priced per hour of generated speech at $0.70, so it cannot be placed on a per-character list without assuming a speaking rate, and it is left out.

Sume's rate and what it means

Sume TTS 1.0 is the provider list of $0.038 per 1K characters times 1.25, which is $0.0475, billed per request up to 20,000 characters (a full request is $0.95). Spaces and punctuation count as characters. Check the current figure on the API pricing page.

• Against the cheapest rate in the list ($11): about 4.3 times.
• Against the $30 group: $17.50 more per million.
• Against Flux TTS ($45): $2.50 more per million.

Budgets at three volumes

Per-million prices are easy to misjudge, so here are four of the rates at three monthly volumes. Each cell is characters in millions times the per-million rate, with no free allowances, plan fees or taxes applied. Speechmatics is left out because its first million characters are free, which changes the shape of the curve.

A practical way to use the list

Take your monthly character count, multiply by the rate in the last column and divide by one million. At 5 million characters a month, Rime Mist v3 is $150, Sume is $237.50 and Rime Coda is $250. The spread between the cheapest and the most expensive entry on the list is $139 per million, so it matters far more than the $2.50 difference between neighbours at the Sume end.

Decide on voice first, then use this list to see what the voice you chose costs on each service that offers it. Most voices are exclusive to one vendor, so the real choice is often between two or three comparable voices, and in that case the per-million gap is a tiebreaker, not the main reason. Budget with the rate you will actually pay, not the cheapest one on the page.

Sources

Rates are from Speechmatics, Deepgram, Cloudflare, Microsoft AI, Rime and Hume. Re-read each before you use a number in a budget.