HotCRP

HotCRP is conference-management software for collecting papers and running peer review through program committee decisions. It is best suited to academic organizers who need a configurable review workflow and can either operate a server or pay for hosted service. Its main strength is the depth of its conference-review tools; independent organizers should weigh the per-submission charge and limited support.

Overview

HotCRP brings submissions, reviewer assignments, review rounds, and committee decisions into one workflow. Blind review, mixed submission types, and a schedule builder make it useful across a conference’s paper process, though it is focused on review rather than general event management.

Organizers can use the open-source software on their own server or choose hosted HotCRP.com. Self-hosting requires Nginx, PHP 7.3 or higher, MariaDB, and several PHP packages, so it suits teams able to maintain that stack. The hosted service avoids server operation, but its privacy terms and support boundaries merit attention before entrusting it with submissions and reviews.

Key features

Submission and assignment

Customizable forms, optional registration, program committee conflict collection, and configurable PDF checks let chairs tailor intake to their process. Papers can be assigned manually, in bulk, or automatically, including through globally optimal automatic review assignment. That range gives chairs flexibility as workloads change, while the quality of assignments still depends on the review and conflict information available to the committee.

Review and decisions

Custom review forms, LaTeX math, multiple rounds, offline reviewing, delegation, and external reviewer invitations support demanding review processes. Committee tools cover rebuttals, votes, rankings, a live meeting tracker, custom decision types, and mailing users. These features make HotCRP a strong fit when paper evaluation and program committee decisions are central; teams seeking broader event operations may need another product.

Search, integrations, and API

Search and sorting by criteria, bulk downloads, arbitrary formulas, and paper tags help chairs manage a large submission pool. HotCRP.com integrates with ACM publication services for copyright forms, final versions, PDF checks, proceedings construction, and Digital Library file export. USENIX uses HotCRP for all its conferences and workshops.

The REST API uses bearer-token authentication, with tokens that can be scoped to read-only access or a subset of papers. That makes controlled access possible for integrations without granting every token broad permissions.

Pricing

HotCRP is freemium, with plans aimed at sponsored conferences, classrooms, testing, and independent events. The free options are conditional rather than a general free tier for any conference.

• ACM-sponsored — free: for ACM-sponsored conferences, journals, and workshops.
• USENIX-sponsored — free: for USENIX-sponsored conferences, journals, and workshops; the site must be created by USENIX.
• Classroom — free: for teachers at educational institutions, subject to approval and evidence of actual classroom use. It includes no support.
• Free test site — free: useful for evaluation, but subject to email restrictions and a limited lifetime.
• Independent — $7.50, paid once: payment of $7.50 per submission is due after the submission deadline. It covers independent conferences, journals, and workshops, with support limited to bug fixes. Costs therefore rise with submission volume, and organizers should plan for the total rather than treat it as a flat event fee.
• IEEE-sponsored — custom pricing: for conferences, journals, and workshops financially sponsored by IEEE; payment is due after the submission deadline.

The sponsored plans suit qualifying organizations that want HotCRP without a per-submission charge. Independent organizers get the hosted service without running their own server, but trade a predictable fixed license for a charge tied to submissions and narrow support. Classroom use is only appropriate when the educational-use conditions are met.

Platforms

HotCRP supports web use, Linux, self-hosting, and an API. The hosted service is the simpler operational choice; the self-hosted option gives organizations control over running the software but requires the stated web-server and database stack.

Who it's for

HotCRP is a good choice for academic conference chairs managing blind, multi-stage review and committee decisions, especially when assignment controls, review rounds, and publication handoff matter. It is less suitable for teams seeking general event management, or independent organizers who need extensive support or a fee that does not scale with submissions.

Pros and cons

• Pros: Covers the paper process from configurable submission through assignments, reviews, rebuttals, and committee decisions, reducing the need to split core review work across tools.
• Pros: Offers manual, bulk, and globally optimal automatic assignments, plus scoped API tokens for controlled access.
• Pros: ACM publication-service integration supports copyright, final-version, proceedings, and export tasks.
• Cons: Self-hosting requires a specific server and database stack, which adds operational work.
• Cons: Independent hosted use costs $7.50 per submission, due after the deadline, and support is limited to bug fixes.
• Cons: Classroom service has no support, and free test sites have email restrictions and limited lifetimes.
• Cons: HotCRP.com states that submission and review artifacts may be stored indefinitely; site managers control access, but organizations should consider this alongside their own retention needs.

Alternatives

For a broader comparison, see Call for Papers Software and Event Abstract Management Software.

Fourwaves is worth comparing for organizers who want a freemium option with web, Android, and iOS support; its Starter plan includes 25 abstract submissions per year, unlimited registrations and events, and a 3% service fee.

ConfTool may suit smaller non-commercial events looking for a free license on request, with local installation, a cap of 150 participants, and no support.

MeetingHand Abstract Management offers a free plan capped at 25 registrations or abstracts, making it a limited-volume alternative to consider.

Sessionize may be a fit for free community events; its free Community event plan excludes internal, private, promotional, marketing, profit, or commercial events.

SimplyConf offers a free Core plan with unlimited events, submissions, and users, for organizers who want a self-hosted or web alternative.

Airballoon is another freemium alternative, with a companion event and networking app included at no additional charge on its BalloonUp plan.

OpenConf is a self-hosted alternative whose Community Edition covers three or fewer events and journals per calendar year.

AbstractWiz offers a free per-event plan for up to 20 submissions, while its paid Standard plan provides unlimited submissions and all features.

Verdict

Choose HotCRP if your conference needs a capable, multi-stage paper-review workflow with substantial committee tools, and you can meet its hosting or per-submission terms. Look elsewhere if you need broad event management, substantial support as an independent organizer, or a hosted fee that stays fixed as submissions grow.