Work out the new flow ratio
Choose the method you printed, then enter your current flow ratio and the modifier on the best block.
Tools
Flow rate calibration
Print OrcaSlicer's flow test, pick the smoothest block, and turn its number into your new flow ratio.
Free tool · no signup
Run the test in OrcaSlicer
Pick the filament
Select the printer and the exact filament profile. The test starts from that profile's current flow ratio.
Print the test
Open Calibration, then Flow ratio, and choose YOLO (Recommended). Slice and print the eleven blocks.
Find the best block
Look for the smoothest top surface with no gaps between the lines. Note the modifier printed on it.
Save the new value
Enter your current flow ratio and that modifier above, then save the result in the filament profile.
The formulas
YOLO: new flow ratio = current flow ratio + modifier. From 0.98 with the +0.01 block, the new value is 0.99.
2-pass: new flow ratio = current flow ratio × (100 + modifier) ÷ 100. From 0.98 with the +5 block, pass 1 gives 1.029. Pass 2 then refines it with modifiers from -9 to 0.
Both are from OrcaSlicer's flow ratio guide.
Common questions
Too low leaves gaps between lines and weak layers. Too high leaves excess plastic, rough surfaces and parts that come out off-size.
Each filament profile stores its own flow ratio, so calibrate each brand and type you use.
Yes, on a printer that lets you set e-steps. E-steps fixes how much the extruder pushes; flow ratio then tunes each filament.