HexaCalc
Free color tools: palettes, pickers, contrast, converters
What is HexaCalc?
HexaCalc is a free color toolkit that lives in your browser. Start with any color in hex, rgb(), hsl(), oklch() or a CSS name and you get every other format, the closest named color and a contrast score for white and black text. From there, the palette generator lets you lock the colors you like and shuffle the rest, the color wheel shows complementary, triadic and analogous schemes, and the image picker pulls colors from a photo, your camera or anything on your screen. There are also gradient and shade generators, a WCAG contrast checker, a color blind test and simulator, and converters for hex, RGB, HSL and CMYK. No account, no install.
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FounderPlaybooks.
What other founders did to grow.
2722 dispatches from hundreds of founders, pulled from the week's best podcasts.
Just being deliberate and saying every single day have at least one customer conversation is super powerful to stay plugged in and not just think of people as a bunch of numbers.
Talk to a Customer Every Single Day — Data Without Context Runs Blind Experiments
Sean Ellis discovered this discipline at Logged Me In: a VC who kept asking 'when did you last talk to a customer?' forced him into daily conversations. The payoff wasn't just softer insights — he ran measurably better experiments because he had so much more context. The survey identifies which customers to call; the call gives the qualitative texture the survey can't capture.
you can use AI to scan the app store every day look for copycat apps we've built stuff at Fabulous to do this we look at the app store every day we're looking at stuff that's rising virally we're scanning it we're looking at the ads that they run and so we have defense mechanisms for this.
Use AI to scan the App Store daily for copycats — the defensive use case is as powerful as the offensive one
Seufert flips the copycat conversation: AI is a defensive weapon, not just an offensive one. At Fabulous, he built automated App Store scanning to detect rising copies and analyze their ads in real time. The lesson from years of creative copying is that it accelerates the need for a repeatable creative production process — companies that continuously generate winning creatives pull away while copycats eat crumbs.
There's a play for whatever you're stuck on.
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