How do you measure performance?

What you see on every converter

On every converter page, you'll notice a performance indicator in the file drop area that looks like this:

This isn't a marketing claim—it's a live statistic calculated from the last 10,000 real conversions. We display this so you know exactly what to expect before you drop your files.

Why we measure

Our goal is to be the fastest bulk file converter online. "FAST" isn't just our name—it's a promise we hold ourselves to.

By measuring and publishing these numbers—and tracking trends over weeks and months—we can see exactly where we're living up to that promise and where we're falling short. If a converter is slower than it should be, we know about it and can prioritize improvements. Transparency keeps us honest.

Why median, not average?

We report the median (P50) processing time because it better represents what most users experience. Unlike averages, the median is not skewed by outliers—a few unusually large files or network hiccups do not distort the number.

If you see "334ms", that means half of all conversions completed faster than 334ms and half took longer. It is a fair, representative measure.

Sample size: 10,000 jobs

Each converter's performance metric is calculated from the last 10,000 completed jobs for that specific conversion type. This gives us a statistically meaningful sample while staying responsive to infrastructure changes.

For high-volume converters (like HEIC to JPG), this represents recent activity. For lower-volume converters, the sample may span a longer time period, but still reflects real-world performance.

What is measured?

The displayed time measures queue time plus processing time—from when your file enters our job queue to when the converted output is ready. This excludes:

• Upload time — Depends on your internet connection and file size
• Download time — Depends on your internet connection

We include queue time because it reflects the real wait you experience. Your total experience (upload → convert → download) also depends on your network conditions, which we cannot control.

How often do metrics update?

Performance statistics refresh every 15 minutes, recalculated from the last 10,000 jobs for each converter.

Per-page metrics for documents

For document converters (PDF, Word, Excel, PowerPoint), we show time per page or per slide. This makes the metric meaningful regardless of document length—a 100-page PDF naturally takes longer than a 5-page one, but the per-page time remains comparable.

Document conversion scales linearly with page count. At ~85ms per page, a 10-page PDF converts in less than a second. A 100-page document? Around 8.5 seconds. Converting an entire library of reports? Fast, predictable, and efficient.

Per-minute metrics for audio and video

For audio and video converters (MP3, WAV, M4A, M4B, OGG, FLAC, and video-to-audio extraction), we show time per minute of content. This makes the metric meaningful regardless of file duration—a 3-hour audiobook naturally takes longer than a 3-minute song, but the per-minute time remains comparable.

Audio conversion is remarkably fast. At ~250ms per minute of content, a 1-hour audiobook converts in approximately 15 seconds. A 3-hour M4B file? Under a minute. Batch converting an entire podcast library? Minutes, not hours.