Frequently asked questions
What PIDoctor does, what it needs, and how to use its recommendations — in short.
What is PIDoctor?
PIDoctor is a free web tool that automatically analyzes your Betaflight blackbox log. You upload the log, describe your build, and get a deep tuning diagnosis — FFT spectra, step response, filter effectiveness and a tune score — plus ready-to-paste CLI commands for both PIDs and filters.
Is PIDoctor free?
Yes. The analysis is completely free and works without an account. Voluntary donations are possible via Stripe, but nothing is hidden behind a paywall.
Does PIDoctor analyze filters, not just PIDs?
Yes — filters and noise are a core strength. PIDoctor shows FFT spectra of the gyro (filtered and unfiltered) and the D-term with the filter cutoffs overlaid, so you can see whether your filters cut where the noise actually sits. It detects motor noise, D-term noise and poor filter effectiveness, and outputs concrete CLI commands for gyro/D-term lowpass, dynamic notch and the RPM filter. Because the tune score separates noise/filters from the PID metrics, you can tell straight away whether your problem is the filters or the PIDs.
Which log files are supported?
Betaflight blackbox logs (.bbl / .bfl), recorded from onboard flash or a blackbox module. For the deepest filter analysis the log should include the unfiltered gyro (via the debug mode).
How do I log for the best analysis?
In the Betaflight blackbox tab, set a sufficient sample rate and pick a debug mode that also records the unfiltered gyro (ideally the D-term values too). Then fly a few deliberate stick inputs per axis. If data for the full filter analysis is missing, PIDoctor tells you honestly instead of guessing.
Do I need an account?
No. You can upload a log and see the full analysis without an account. An account only stores your flights and builds for later.
What happens to my log files?
Your log is transferred to the server and processed for the analysis. The result page is set to noindex, so it is not publicly discoverable in search engines. Exactly what is stored is described in the privacy policy.
What is the tune score?
The tune score is an overall rating from 0–100 with a grade, made up of several sub-scores: tracking and step response (PIDs) as well as noise and filter effectiveness. That lets you see at a glance where your tune stands and which dimension is the actual problem.
Which Betaflight versions does it work with?
PIDoctor reads logs from Betaflight 4.x and adapts the suggested CLI commands to the detected firmware version, so the commands match your version.
Can I apply the CLI commands directly — is it safe?
The commands are suggestions, not instructions — review them before applying. On a computer you can connect your flight controller over Web Serial and send the commands directly; always take the propellers off first. The decision and responsibility rests with you (see the terms of use).