Enter your sample volume and get the smallest cuvette that fits — from 20 µL ultra-micro to long-path cells.
Enter your available sample volume — we will recommend the smallest cell that fits, so you waste the least sample.
| Cell type | Usable volume | Best for |
|---|---|---|
| Ultra-micro (20 µL) | 10 – 20 µL | Precious samples, fluorescence, low-volume assays |
| Ultra-micro (50–200 µL) | 40 – 200 µL | Most routine low-volume UV-Vis & fluorescence |
| Micro (700 µL) | 200 – 700 µL | Standard sub-micro analysis |
| Semi-micro (~1.5 mL) | 700 µL – 1.5 mL | Compromise between macro and micro |
| Macro (3.5 mL) | 1.5 – 3.5 mL | Standard 10 mm work, matching pairs |
| Long-path (20–100 mm) | 4 – 40 mL | Trace analysis, very dilute samples |
Related: Cuvette Care Guide · Path Length Guide · Size Calculator · Path Length Calculator · Brand Alternatives · Contact Scuvette
Need a hand? Our engineers can help you select the right cuvette for your instrument and application — or supply custom optical cells to your drawing. Contact Scuvette →Match three things: the light path your method needs (usually 10 mm), the internal volume to your sample amount, and the outer dimensions to your instrument's cell holder. Standard 10 mm cells hold about 3.5 mL total and need roughly 1 mL of sample to fill the beam.
If you have limited sample, use a semi-micro cell (about 1.5 mL), a micro cell (100 to 400 microlitres) or an ultra-micro cell (down to about 35 microlitres). The calculator converts your available volume into the smallest cell that still fills the beam path.
Outer size does not; the optical path length does. You only need enough volume to cover the light beam. Too little sample leaves the beam path partially empty and gives a falsely low or noisy reading.
Most holders accept the standard 12.5 by 12.5 by 45 mm cell. Some instruments require a specific height or a rectangular rather than square format, so check the holder specifications before ordering an unusual size.
Macro cells use the full volume of about 3.5 mL; semi-micro keep the standard footprint but reduce the required volume to about 1.5 mL; micro and ultra-micro use small apertures and shorter fill heights for microlitre samples.