Select focal lengths to compare field of view (full-frame).
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About Focal Length
Most online tools for this task bury what you need behind ads and forms. Focal Length takes the opposite approach: load the page, do the job, leave. Everything happens client-side, which means your files and data never leave your machine. The interface is intentionally minimal so you can focus on the task instead of learning the tool. If you find yourself doing this regularly, the rest of the utility suite covers most adjacent tasks with the same approach.
When you'd reach for Focal Length
You're hitting the daily limit of a paid SaaS and need a backup option for a single quick job.
Marketers and ops people whose primary tool is metered.
Stay productive without burning credits.
You're cleaning up a folder of files that accumulated over a project and need to standardize them.
Designers, writers, and developers wrapping up deliverables.
Drop each file in, copy the output, move on.
You're on a public or shared machine and don't want to leave traces of what you're working on.
Travelers, contractors, anyone working from a friend's computer.
Nothing is uploaded, nothing persists if you're not signed in.
You need to handle a one-off task right before a meeting and don't have time to install anything.
Anyone working remotely on a borrowed or restricted machine.
Open the page, get the result, paste it into your doc — under a minute.
Frequently asked about Focal Length
- Is Focal Length really free?
- Yes — Focal Length is free for unlimited personal use, with no account required and no watermark on the output.
- Are my files uploaded to a server when I use Focal Length?
- Focal Length processes everything in your browser using local APIs. Your files never leave your device.
- Does Focal Length work on mobile?
- Yes, Focal Length is fully responsive and tested on iOS Safari and Android Chrome.
- Will Focal Length change my original file?
- Never. Focal Length only reads your input file and produces a new output file.
- Do I need to create an account to use Focal Length?
- No. Focal Length works without any signup. We only ask for an email if you decide to subscribe to a paid plan.