Free
$0
5 images · 10 measurements per IP / 10 min RGB · CMYK · Lab · basic CSV Project save/restore · background correction
Start measuring1. Open the three example images. 2. Select ROIs inside each color pad. 3. Measure and link a separate background ROI. 4. Export raw and corrected values as CSV. Paid: preview and apply the ROI template to other images with the same arrangement.
Uses browser-decoded, original-resolution 8-bit sRGB pixels. Only pixels inside the ROI bounding rectangle are sent over an encrypted connection. The server handles circle masking, alpha exclusion and RGB/CMYK/Lab computation. CMYK/Lab are converted per pixel before averaging. CIELAB uses D65/2°; CMYK is arithmetic without an ICC profile. Photos do not replace a calibrated colorimeter. Keep lighting, camera and exposure consistent.
Correction = sample mean RGB − background mean RGB. Negative values are retained; raw Lab/CMYK are unchanged. A background ROI counts as one measurement.
RGB · sRGB 0–255 · mean of opaque pixels
CMYK · 0–100% · mean of per-pixel arithmetic conversions. Not an ICC-profiled print measurement.
CIELAB · D65 / 2° · L* 0–100, signed a* and b*. Mean of converted sRGB pixels, not a calibrated colorimeter measurement.
Use files up to 50 MB and ROIs up to 4 million pixels.
5 images · 10 measurements per IP / 10 min RGB · CMYK · Lab · basic CSV Project save/restore · background correction
Start measuring60 minutes from successful payment · no renewal
No plan limit on image or measurement counts Fixed ROIs · move · resize · duplicate ROI templates · batch application · combined CSV
One-time payment · no recurring charge
No plan limit on image or measurement counts Fixed ROIs · move · resize · duplicate ROI templates · batch application · combined CSV
Users sharing a public IP (such as lab Wi-Fi) share the free allowance. It resets 10 minutes after first use. IPv6 is grouped by /64 network. Free workspaces hold up to 5 images at once. File-size, ROI-pixel and request-burst safeguards apply to all plans.
Save your recovery key after purchase. For payment issues or refund requests, include the receipt identifier in the contact form below. Never send card numbers or recovery keys.
Use this key to restore access on another device. Keep it private like a password.
Start measuringSend an issue or feature suggestion. Do not include experimental images or sensitive information.
Measurements: ROI pixels are processed in server memory and are not stored as files or database records. Original image files and sample names are not sent. If an ROI covers the whole image, all its pixels are sent. Device storage: project files and autosaves contain images, ROIs and results. Delete device backups on shared computers. Usage: we store a keyed pseudonymous IP identifier and counters, not the raw IP. Expired records are cleaned daily. Hosting providers may process connection information for security and operations. Payments: Stripe processes card details. The app retains payment identifiers and access status, not card numbers. Contact: email and messages are retained up to 90 days. No ad or tracking scripts are active. This notice and required consent settings will be updated before ads are enabled.