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Apollo.io
Project EulerWe use Apollo with our Sales and BDR team to manage our cold outreach. The strength of the platform is the sequences and cadences that you can set up. Compared to other tools we have used in the past like Salesloft the UI is much easier to navigate. The main limitation is that the quality of data isn't as vast and often I can find prospects on Linkedin but not in Apollo.
Based on our record, Project Euler should be more popular than Apollo.io. It has been mentiond 415 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Personal email domains destroy this. Clearbit's Enrichment API returns a null company when it hits gmail.com. Apollo routes personal domains straight to a consumer bucket and skips B2B fields entirely. Even PDL's /person/enrich endpoint โ the most permissive of the major providers โ gives you around 32% hit rate on Gmail addresses versus 74% on corporate domains. I measured this across 6,200 signups for a... - Source: dev.to / about 1 month ago
A few things worth flagging: PDL beats Clearbit's historical rates for US and Western European companies, but drops to ~52% match rate for Japan and South Korea specifically. Apollo underperforms on raw company matching but returns significantly more contacts per domain in Prospector-style queries than Clearbit's Prospector ever did โ the tradeoff is more stale titles in the result set. Hunter.io is fast and cheap... - Source: dev.to / about 2 months ago
One thing comparison guides consistently get wrong: Clay is not an enrichment API. It's a waterfall orchestration tool that calls People Data Labs, Apollo, Clearbit, and others in sequence for you. It's useful, but it adds 2โ8 seconds of latency per row in my runs and costs more per match than going direct. For a CRM webhook flow where you need sub-second enrichment calls, Clay is the wrong layer to hit first. - Source: dev.to / 2 months ago
Last year I ran the same LinkedIn Sales Navigator export through three enrichment APIs. Apollo matched 61% of the emails. Hunter.io matched 54%. An OSINT-first pipeline I'd built in n8n โ pulling from public sources before hitting any paid API โ matched 79% and cost roughly $0.003 per contact. The delta wasn't magic. It was sequence. - Source: dev.to / 2 months ago
Despite having its LinkedIn Page removed in 2025, Apollo remains a functional enrichment and outreach platform with 275M+ contacts. The free tier includes 10,000 credits and the $49/month basic plan is the cheapest entry point for a combined enrichment-plus-sequencing workflow. Apollo's data collection methods have attracted LinkedIn's attention, but the product continues to operate. The risk I'd assign it:... - Source: dev.to / 2 months ago
Let's hope this is going to help me solve some more Project Euler [1] problems! [1] https://projecteuler.net/. - Source: Hacker News / about 2 months ago
Https://projecteuler.net/ for "Thinker" brain food. (it still has the issue of not being a pragmatic use of time, but there are plenty interesting enough questions which it at least helps). - Source: Hacker News / 5 months ago
I have a Project Euler (https://projecteuler.net/) account. Though I do not register at all on the leader board I will sometimes work obsessively on a problem just to make one of the level icons light up for me. There is not really competition just a tiny reward. - Source: Hacker News / 7 months ago
I do hobby programing. It is sometimes to create something (supposedly) useful. Lately though it is more discovery and a little math like. I enjoy Project Euler (https://projecteuler.net/. Recently I have been playing with superpermutations (https://projecteuler.net/) and pencil and paper is useful but filling lots of paper with lots of numbers is not that fun. - Source: Hacker News / over 1 year ago
As pointed out in a sibling comment, it appears that quote only shows up if you're logged in, but assuming you have an account and are logged in, it's on the homepage (https://projecteuler.net/), second paragraph under the following heading: > I learned so much solving problem XXX, so is it okay to publish my solution elsewhere? > It appears that you have answered your own question. There is nothing quite like... - Source: Hacker News / over 1 year ago
ZoomInfo - ZoomInfo is a B2B database providing detailed business information on people and companies.
LeetCode - Practice and level up your development skills and prepare for technical interviews.
Lusha - Search less. Sell more.
Exercism - Download and solve practice problems in over 30 different languages.
Hunter.io - Find all the email addresses related to a domain
Codewars - Achieve code mastery through challenge.