audio model comparison

AssemblyAI-TTS-1 vs Eleven Flash v2.5

AssemblyAI-TTS-1 and Eleven Flash v2.5 are both current audio models, from AssemblyAI and ElevenLabs. AssemblyAI-TTS-1 is 63% cheaper per character than Eleven Flash v2.5, $0.000015 vs $0.00004. On Artificial Analysis Speech Arena, AssemblyAI-TTS-1 scores 1221 Elo and Eleven Flash v2.5 1075 Elo (Artificial Analysis, measured November 3, 2026).

Higher Artificial Analysis Speech Arena: AssemblyAI-TTS-11221 Elo against 1075 Elo
Lower price per character: AssemblyAI-TTS-1$0.000015 against $0.00004

Data verified November 3, 2026 · Dataset 2026-11-03

AssemblyAI-TTS-1 and Eleven Flash v2.5, line by line

Prices in effect today, compared at the same tier wherever both list one. The better value in each row is highlighted.

Fact	AssemblyAI-TTS-1	Eleven Flash v2.5
Price
Price per character	$0.000015 (better)	$0.00004
Independent benchmarks
Artificial Analysis Speech Arena	1221 Elo (#6 of 13) (better)	1075 Elo (#12 of 13)
Specs
Provider	AssemblyAI	ElevenLabs
Release date	October 28, 2026	Not reported
Access	API only	API only
Context window	Not reported	Not reported
Max output	Not reported	Not reported
Input	text	text
Output	audio	audio

Scores:Artificial Analysis · 2026-11-03

Open both in the interactive comparison

Charts

Against every current audio model

Where AssemblyAI-TTS-1 and Eleven Flash v2.5 land among the current models of their task, on every independent benchmark, on price and on context.

Where each stands

On Artificial Analysis Speech Arena, AssemblyAI-TTS-1 ranks #6 and Eleven Flash v2.5 #12 of 13 current models. Each bar is the share of current models it beats: on score, price and context.

Independent benchmarks

Artificial Analysis Speech Arena

AssemblyAI-TTS-1:#6of 13

1,221 Elo · ahead of 58%

Eleven Flash v2.5:#12of 13

1,075 Elo · ahead of 8%

Price and context

Price per character

AssemblyAI-TTS-1:#2of 11

$0.000015 · cheaper than 70%

Eleven Flash v2.5:#6of 11

$0.00004 · cheaper than 40%

Scores fromArtificial Analysis · 2026-11-03

Cost

What each costs

Example workloads at each provider's listed rates, then every other rate either one lists. The cheaper figure in each row is highlighted.

The same work, priced

For 1M characters, Eleven Flash v2.5 costs 2.7 times as much as AssemblyAI-TTS-1, at each provider's listed rates.

1M characters
Eleven Flash v2.5 costs 2.7× as much
AssemblyAI-TTS-1
$15
Eleven Flash v2.5
$40

Workload or rate	AssemblyAI-TTS-1	Eleven Flash v2.5
Example workloads
1M characters	$15 (better)	$40

Your own bill will differ. These figures use list prices and example workloads. The AI Model Cost Audit reviews your real usage, shortlists models that score as well for each task for less, and estimates the savings.

Launch price $100, regular price $150

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Verdict

When to choose each

AssemblyAI-TTS-1

Where it leads

Lower price per character, $0.000015 vs $0.00004
Higher Artificial Analysis Speech Arena score, 1221 Elo vs 1075 Elo

Best for

Voice agents on live phone calls
High-volume speech where the cost per character matters

Watch out for

Six languages at launch; AssemblyAI says more languages and accents will follow
No fine-tuned (Pro) voice cloning, pronunciation dictionaries or emotion tags at launch
The head-to-head figures in the launch post are AssemblyAI tests

Full AssemblyAI-TTS-1 profile

Eleven Flash v2.5

Where it leads

Supports realtime voice

Best for

Low-latency multilingual speech

Watch out for

Built for latency rather than expressiveness; Eleven v4 Turbo now sells at the same $0.04 per 1,000 characters

Full Eleven Flash v2.5 profile

From benchmark to production

Building on AssemblyAI-TTS-1 or Eleven Flash v2.5?

Public scores rarely hold on your own data. We test both models on your real tasks, then build the agent or pipeline around the one that wins.

AI Model Cost AuditLaunch price $100, regular price $150What the audit includes

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