Online Bike Fit at Home: How AI Can Help You Check Your Riding Position

A bike can be the correct size on paper and still feel wrong when you ride it. Your saddle may be slightly too high, your reach may feel excessive, or your position may leave you feeling less comfortable than expected after longer rides.

Traditionally, investigating those problems meant booking an appointment with a bike-fitting studio. That remains an important option, particularly for riders dealing with persistent pain, injury, complex biomechanical issues, or high-level performance requirements. But cyclists who simply want an objective check of their basic riding position now have another option.

BikeFit/LAB provides an online bike fit at home using a phone or webcam. You record yourself pedalling, the software analyzes your riding position in the browser, and you receive a report showing measured joint angles and suggested adjustments.

For road, gravel, mountain, city, and triathlon riders, it offers a straightforward way to examine saddle position, reach, posture, and other key measurements without visiting a fitting studio.

What Is an Online Bike Fit?

An online bike fit uses photographs or video to estimate how your body is positioned while riding.

BikeFit/LAB takes this a step further by using pose-estimation technology to identify body landmarks and measure movement through the pedal stroke.

The standard process involves recording approximately 12 seconds of side-on pedalling. According to BikeFit/LAB, its system measures nine key metrics and analyzes angles including the knee, hip, torso, and elbow throughout the pedal cycle.

The aim is not simply to display a collection of numbers.

The resulting measurements are compared with reference ranges based on the bike type and riding goal you select. The software then turns those measurements into practical suggestions concerning areas such as saddle height, saddle fore-and-aft position, and reach.

That makes the result easier to interpret for riders who do not have a background in cycling biomechanics.

How an AI bike fit Works

The technology behind BikeFit/LAB uses MediaPipe Pose, a computer-vision pose-estimation system.

When you provide a side-view recording, the software identifies body landmarks frame by frame. It then calculates joint angles across the pedal stroke rather than relying on one frozen photograph.

This distinction is useful because cycling is a repetitive movement.

Your knee angle changes continuously as the crank rotates. Your hip opens and closes. Your upper body position can also vary depending on the way you are pedalling.

Analyzing multiple frames provides a broader picture than measuring a single image.

BikeFit/LAB also uses the rider's inseam measurement when translating changes in angles into adjustment suggestions expressed in millimetres.

That does not mean a camera-based system can reproduce every measurement available in a professional 3D bike-fitting studio. BikeFit/LAB itself identifies limitations including cleat position, saddle width, and certain left-to-right asymmetries that may require more detailed assessment.

Think of the system as an accessible position check rather than a replacement for every form of professional fitting.

What You Need to Complete the Fit

The ideal setup is relatively simple:

• your bicycle,
• an indoor trainer or rollers,
• a phone, tablet, or webcam,
• adequate lighting,
• enough room for a clear side view,
• and fitted clothing that makes body position easier for the camera to identify.

BikeFit/LAB recommends positioning the camera side-on to the bicycle, approximately two to four metres away, with the lens around saddle height. The complete rider and bicycle should remain visible in the frame.

Getting the camera position right matters.

A camera placed at a strong angle to the bike can distort apparent joint angles. Loose clothing can also make accurate landmark detection more difficult.

Spend a few minutes preparing the recording area before beginning. A cleaner input gives the software a better opportunity to produce useful measurements.

What If You Do Not Own an Indoor Trainer?

An indoor trainer produces the most complete analysis because you can pedal naturally while remaining stationary.

However, BikeFit/LAB does not require one.

The service provides alternatives for riders who do not have a trainer. You can support the bicycle against a wall or have someone hold it while you pedal slowly backwards. Another option is uploading four side-view photographs corresponding to the crank positions at approximately 12, 3, 6, and 9 o'clock.

These alternatives make an online fit accessible to more recreational riders.

The important point is to understand that different recording methods may provide different levels of information. A proper trainer setup allows analysis of continuous pedalling, while static images provide snapshots of specific positions.

If you have access to a trainer, use it. If you do not, the alternative methods can still provide a useful starting point.

What Does the Bike Fit Measure?

A bike fit is ultimately about relationships between the rider and the bicycle.

Saddle height affects knee extension. Saddle fore-and-aft position changes the rider's relationship to the pedals and cockpit. Reach and handlebar position influence torso and elbow angles.

BikeFit/LAB measures these relationships using pose estimation and compares them with ranges appropriate to the selected bicycle category and riding goal.

Importantly, the same position is not treated as ideal for every cyclist.

Someone riding a city bike for comfort should not necessarily be assessed against the same targets as someone using an aggressive road-racing position.

BikeFit/LAB allows users to select their bicycle type and riding objective, including different goals for road and gravel setups.

That gives the analysis more context than a single universal angle target.

Turning Measurements Into Practical Adjustments

Numbers are only useful when you know what to do with them.

The BikeFit/LAB report is designed to move from measurement to action.

Instead of simply showing that your knee extension is outside a target range, the system can recommend a change to saddle height. Likewise, measurements associated with reach can lead to suggestions concerning the cockpit or saddle position.

The report includes recommended adjustments expressed in millimetres and explains the order in which changes should be considered.

This matters because changing several things simultaneously makes it difficult to understand which adjustment actually improved or worsened your position.

A more sensible process is:

1. Measure your starting position.
2. Review the highest-priority recommendation.
3. Make a small adjustment.
4. Ride the bike.
5. Allow time to adapt.
6. Measure again if necessary.

Bike fitting is often an iterative process rather than one dramatic change.

Your Personal Coaching Report

After completing an Online AI bike fit, BikeFit/LAB generates a coaching report rather than only presenting measurements on screen.

The report includes a visual representation of riding position, measured joint angles, plain-language explanations, adjustment recommendations, mobility suggestions, and a structured schedule for introducing changes. It can be downloaded as a PDF and is also delivered by email.

That gives riders something they can save and refer back to.

You might complete a baseline measurement at the start of the season, make adjustments, and then repeat the fit later to see how the position has changed.

For cyclists with more than one bike, reports can also make it easier to compare setups.

A road bike, gravel bike, and indoor training bike may not require identical positions, but having measurements for each can help you understand the differences rather than relying completely on how they appear visually.

Privacy: Your Video Stays on Your Device

Uploading a video of yourself to an unknown server may understandably make some riders uncomfortable.

BikeFit/LAB takes a browser-based approach to video processing.

According to its privacy explanation, the pose-estimation analysis runs locally in the browser. The original riding video is not uploaded or stored on BikeFit/LAB's server. Only the resulting measurements are transmitted for generation of the report.

This is an important distinction.

The software needs the visual information long enough to calculate body landmarks, but the source video itself remains on the user's device.

For privacy-conscious cyclists, local processing can be one of the more attractive characteristics of this type of service.

Road, Gravel, MTB, City and Triathlon Bikes

BikeFit/LAB is designed for multiple styles of cycling rather than one specific discipline.

The website currently lists support for:

• road bikes,
• gravel bikes,
• mountain bikes,
• city bikes,
• and triathlon/time-trial bikes.

This matters because riding position varies significantly between categories.

A city rider may prioritize a relaxed and upright posture. A road cyclist may want a compromise between aerodynamics, comfort, and sustainable power. A time-trial rider may be working with a much more aggressive position.

Choosing the appropriate bike type at the beginning allows the system to interpret your measurements in the correct context.

It also means someone with several bicycles can assess each bike independently rather than assuming one fit should be copied exactly onto every machine.

How Accurate Is Camera-Based Bike Fitting?

BikeFit/LAB is transparent about the limitations of 2D pose estimation.

Its website references research comparing MediaPipe measurements with marker-based systems and notes typical differences of several degrees for knee and hip measurements, with greater variation possible around the ankle.

For practical purposes, that means an AI fit is better viewed as a way of identifying whether your position is broadly inside or outside established ranges than as a clinical tool capable of distinguishing every individual degree.

Camera setup also influences the result.

If your phone is too close, too high, or positioned diagonally, perspective changes can affect the measurements.

Use good lighting, fitted clothing, and a carefully positioned camera. If a result looks unexpectedly extreme, repeat the measurement before making a major adjustment.

Free Bike-Fitting Tools

Not every rider needs a complete fit immediately.

BikeFit/LAB also offers free tools that can help with basic setup questions.

These include a saddle-height calculator and a camera-based bike-size tool.

A saddle-height calculator can provide a starting point when setting up a new bicycle, while bike-sizing tools can help riders explore whether a frame is broadly appropriate before moving into more detailed position analysis.

These should still be treated as starting points.

Two riders with the same height can have different proportions, flexibility, riding goals, and preferences. That is why measuring the actual riding position can provide more useful information than relying exclusively on height-based size charts.

Pay Per Fit Rather Than a Subscription

BikeFit/LAB currently operates using credits rather than a monthly subscription.

A single fit costs €5. A three-fit Rider Pack costs €10, while a ten-fit Season Pack costs €25, bringing the price to €2.50 per fit when purchasing the larger bundle. Credits do not expire.

Each credit includes the measurement and coaching report, with PDF and email delivery.

The multi-fit option is particularly relevant because bike fitting often benefits from repeating the process.

You can measure your starting point, make adjustments, ride for a period, and then re-test.

That creates a simple measure-adjust-review cycle instead of treating the first recommendation as the final answer.

When You Should Choose a Professional Bike Fit Instead

Online fitting has limitations, and BikeFit/LAB explicitly acknowledges them.

If you have persistent pain, numbness, an injury, significant physical asymmetry, or a complex performance issue, professional assessment is the better option.

A studio bike fit can examine factors that a side-view camera cannot fully assess, including cleat alignment, saddle pressure, detailed left/right differences, flexibility, movement patterns, and the physical interaction between rider and equipment.

Likewise, an online bike fit is not medical advice.

If cycling causes persistent or significant pain, consult an appropriate healthcare professional rather than repeatedly adjusting the bicycle in an attempt to diagnose the issue yourself.

BikeFit/LAB positions its service as an accessible riding-position check rather than a replacement for physiotherapy or professional medical assessment.

A Practical Starting Point for a Better Riding Position

You do not necessarily need specialist equipment to begin understanding your position on a bicycle.

With a bicycle, camera, and a few minutes of setup, BikeFit/LAB can measure key aspects of your posture and pedal stroke and turn them into a structured report.

The value is in making your position measurable.

Instead of wondering whether your saddle looks high or whether your handlebars feel far away, you can collect objective measurements, compare them with relevant reference ranges, and make small, deliberate adjustments.

For cyclists who want a convenient and inexpensive starting point, an online bike fit at home offers a way to examine riding position without committing immediately to a studio appointment.

Use the recommendations gradually, pay attention to how the bicycle feels after each change, and remember that numbers are part of the process rather than the entire answer.

Visit BikeFit/LAB to record your position, review the available free tools, or complete an AI-assisted bike fit using your phone or webcam.