API Testing is the process of testing Application Programming Interfaces (APIs) to ensure that they are working correctly and achieving the expected results. APIs are integral for any software applications to communicate with each other, as they provide data exchange and flow of information between different applications. A qualified API Testing Expert can ensure that the communication between applications is secure, and that they meet the performance requirements of the end user.

API Testing Experts make sure to think like an “attacker” while performing API operations, while they expand the boundaries of API inputs to test. This involves traditional testing methods such as boundary value analysis, API workflow validations, boundary conditions and security patch testing. In addition their skills involve overseeing the debugging of API logical codes, assisting in 4GL programming related tools, creating automated API tests & scripts as well as load and stress test API process flows.

Here’s some projects that our API Testing Experts has made real:

  • Creating automated tests for backend services
  • Identifying security loop holes in APIs
  • Debugging API logic codes and component layers
  • Developing customized load tests for optimal performance
  • Integrating third party services via APIs

Overall, a qualified API Testing Expert can provide comprehensive and reliable solution for your application software. These experts can fine tune your application software to ensure that it meets all system requirements and user demands efficiently. By hiring an experienced freelancer from Freelancer.com you can secure superior performance of your application software maintained in perfect condition. We invite you to post your own project on Freelancer.com today and get ready to hire an expert API Tester!

From 16,956 reviews, clients rate our API Testing Experts 4.9 out of 5 stars.
Hire API Testing Experts

API Testing is the process of testing Application Programming Interfaces (APIs) to ensure that they are working correctly and achieving the expected results. APIs are integral for any software applications to communicate with each other, as they provide data exchange and flow of information between different applications. A qualified API Testing Expert can ensure that the communication between applications is secure, and that they meet the performance requirements of the end user.

API Testing Experts make sure to think like an “attacker” while performing API operations, while they expand the boundaries of API inputs to test. This involves traditional testing methods such as boundary value analysis, API workflow validations, boundary conditions and security patch testing. In addition their skills involve overseeing the debugging of API logical codes, assisting in 4GL programming related tools, creating automated API tests & scripts as well as load and stress test API process flows.

Here’s some projects that our API Testing Experts has made real:

  • Creating automated tests for backend services
  • Identifying security loop holes in APIs
  • Debugging API logic codes and component layers
  • Developing customized load tests for optimal performance
  • Integrating third party services via APIs

Overall, a qualified API Testing Expert can provide comprehensive and reliable solution for your application software. These experts can fine tune your application software to ensure that it meets all system requirements and user demands efficiently. By hiring an experienced freelancer from Freelancer.com you can secure superior performance of your application software maintained in perfect condition. We invite you to post your own project on Freelancer.com today and get ready to hire an expert API Tester!

From 16,956 reviews, clients rate our API Testing Experts 4.9 out of 5 stars.
Hire API Testing Experts

Filter

My recent searches
Filter by:
Budget
to
to
to
Type
Skills
Languages
    Job State
    14 jobs found

    NEED TO BE DONE IN LESS THAN 24 HOURS MAKE SURE U DM ME IF UR INTRESTED AND WHAT U BID IS WHAT U GET Work is Done ON ----------------- Objective Recover a competitive API hold path (if still possible) and improve hold performance under heavy competition. Current behavior is mainly: WS + ChartRender fallback Hold-only mode (no auto-checkout) Multi-holder distributed accumulation Primary problem: API hold path is effectively unavailable on target events, so fallback path loses races. What Works Now Event detail fetch works (event_id, event_key, workspace, pricing, limits). Session restore + token bridge works. Seat discovery/polling works. ChartRender selectObjects executes very fast (few ms). Hold-only flow is strict (no checkout automation). What Fails Now API hold endpoints appear dead...

    $136 Average bid
    $136 Avg Bid
    102 bids

    I’m calling the /challenge/v1/continue endpoint with a POST request, sending a JSON payload and passing my API key in the headers, yet the server keeps replying with HTTP 403. I’d like you to pinpoint why the call is being rejected, adjust the headers or signing process as needed, and hand back a fully working example so I can reproduce the success on my end. You’re free to use Postman, curl, or any other HTTP client while troubleshooting; just make sure the solution works consistently once my key is swapped in. Deliverables 1. A tested request sample (curl command or Postman collection) that returns a non-403 response. 2. A concise explanation of the authentication or header changes required so I can apply the fix to other endpoints. # Roblox

    $105 Average bid
    $105 Avg Bid
    103 bids

    Project Title: Defence Flight OTA Research & Architecture Consulting (India) Project Overview: I am planning to build a defence-focused flight booking OTA platform in India similar to: These platforms often show defence fares significantly lower than normal public fares. Before starting development, I want an experienced OTA/travel-tech expert to help analyze how such systems likely work from inventory, API, supplier, and architecture perspectives. Important: This is NOT a direct website development project initially. Phase 1 is a research + consulting + technical planning project. Project Goals: 1. Analyze possible backend/inventory logic used by defence-focused OTAs 2. Research whether fares likely come from: - airline direct contracts, - consolidators, - GDS/priva...

    $99 Average bid
    $99 Avg Bid
    12 bids

    Build a testing framework from scratch for a new website (around 20 pages). A live staging URL will be provided for black-box testing. The objective is to analyze the site, document the core workflows tests in our , and automate them using Cypress. Scope of Work Analyze & Plan: Analyze the live staging site to map out all core functional workflows. Test Case Creation: Write a structured, comprehensive test suite in our using plain English. Automation: Develop Cypress scripts to automate the test cases against the staging URL. Integration: Configure the open-source Cypress framework to sync execution results directly to the Qase dashboard using the Qase reporter plugin. Final verification will take place locally after the delivered files are extracted and run. Deliverables A fully po...

    $133 Average bid
    $133 Avg Bid
    92 bids

    I’m putting our call-center CRM through a full health check and need an experienced tester to lead the effort from test-plan design right through to final sign-off. The focus is on the areas that matter most to day-to-day agents—call handling, secure customer data flow, and the reports managers rely on. You will study the admin too and let us know what needs to be fixed asap It is powered by twilio so you need to have a full understanding of how twilio works

    $20 Average bid
    $20 Avg Bid
    26 bids
    Meta API Tokens Configuration
    14 hours left
    Verified

    I already hold an active Meta developer account, but I need another set of expert hands to turn that account into working, refreshable access tokens for both Facebook and Instagram Threads at the same time. The goal is simple: by the end of the engagement I want you to run a quick test postman call and confirm that I can create, read, and update content on both platforms with a stable, long-lived token. Read-write scope is essential; nothing less will do. What I expect from you • Configure the existing Meta app so that the required permissions for Facebook Pages and Instagram Threads publishing are approved or in review where necessary. • Generate short-lived tokens, exchange them for long-lived ones, and document the refresh workflow so I can repeat it without you later....

    $21 Average bid
    $21 Avg Bid
    61 bids
    Fix Hostinger API Errors
    10 hours left
    Verified

    I’m running a project on Hostinger’s Horizon platform and every API call is currently failing with a “data retrieval error.” The issue isn’t limited to a single route—every endpoint I test returns the same response. All requests are authenticated with an API key, so it’s not OAuth or a basic-auth problem. Here’s what I need: • Diagnose why the Horizon API refuses to return data when an API-key header is supplied. • Implement and test a clean fix—whether that’s correcting headers, adjusting CORS, rewriting routes, or updating server-side settings—until each endpoint delivers the expected JSON response. • Provide a concise report of the root cause and the steps you took so I can reproduce or roll back if n...

    $69 Average bid
    $69 Avg Bid
    45 bids
    Flipkart & Amazon API Testing
    5 hours left
    Verified

    I’m building an internal test bed and need reliable access to both the Flipkart and Amazon affiliate APIs (or any other officially published endpoints) so I can run functionality tests focused purely on product search. My goal is to verify that queries return the correct items, in the right order, with consistent formatting, so I can later layer load and security checks on top of a solid baseline. Need api for 1 week i will give 1000 inr

    $10 Average bid
    $10 Avg Bid
    12 bids

    I’m just getting started with IBM API Connect and would like to master the entire workflow—from writing OpenAPI YAML files right through to exposing them on a working gateway. To get there, I need a mentor who can walk me through the platform in an interactive, hands-on way rather than simply pointing me to documentation or videos. The areas I want to cover include API design and creation, securing and managing those APIs, and finally monitoring, analytics and troubleshooting once everything is live. Live screen-sharing sessions, practical lab exercises and real-world examples are the teaching methods that work best for me. Deliverables • A series of interactive remote sessions that build progressively from beginner concepts to deployment on a gateway • Step-by-st...

    $488 Average bid
    $488 Avg Bid
    61 bids

    I'm looking for an experienced developer to fix existing issues with our API link to Mintsoft WMS. We've been encountering API errors and crashes, especially since a recent update to the Mintsoft system. Key Requirements: - Diagnose and resolve API errors and crashes - Ensure stable and reliable API performance - Collaborate to understand the impact of the Mintsoft update Ideal Skills and Experience: - Strong background in API development and troubleshooting - Familiarity with Mintsoft WMS and its API - Experience with system updates and their implications on API functionality Please provide examples of similar work done.

    $595 Average bid
    $595 Avg Bid
    161 bids

    I need an experienced developer to integrate Supabase edge functions with Documint API for automated PDF report generation. The project involves setting up a complete pipeline that processes AI-generated content (Claude API JSON output) and converts it into professional PDF reports using Documint templates. The system should handle template mapping for headers, data sections, scores, and verdicts, then deliver the final PDFs via email using Resend. Requirements: • Expert-level experience with Supabase edge functions • Strong TypeScript/Deno development skills • Proven experience with Documint API integration • Knowledge of Claude API and JSON data parsing • Experience with Resend email service integration • Ability to create and map PDF templates with dynami...

    $6 / hr Average bid
    $6 / hr Avg Bid
    63 bids

    Minha plataforma já está cerca de 85 % concluída. O que preciso agora é de um(a) profissional que entre, revise o que foi desenvolvido, ajuste eventuais inconsistências e coloque tudo para rodar de forma estável. Principais frentes de trabalho • Testes funcionais, de usabilidade e de desempenho: quero garantir que cada fluxo opere sem erros, ofereça boa experiência ao usuário e mantenha performance aceitável mesmo sob carga. • Criação e acoplamento de uma pequena API de bancos voltada exclusivamente para integração de pagamento — nada de consulta de saldo ou histórico, apenas processar cobranças de forma segura. Entrego acesso ao repositório Git, &agrav...

    $457 Average bid
    $457 Avg Bid
    29 bids

    Quiero desarrollar una solución completa de membresías compuesta por tres capas: La membresía debe registrar todas las empresas del país que deseen dar privilegios a una multitud de clientes que se deben afiliar al sistema por medio de la app o la web. 1. Backend seguro en Spring Boot • API REST documentada (OpenAPI) • Gestión de usuarios, control de acceso por roles, historial de pagos y registro detallado de cada proceso • Integración con pasarelas de pago (Stripe u otra equivalente) • Autenticación JWT y refresco de tokens • Base de datos relacional (PostgreSQL) con migraciones versionadas 2. Panel administrativo web en React + Vite • Dashboard para crear, editar y suspender me...

    $3738 Average bid
    $3738 Avg Bid
    81 bids

    Quiero desarrollar una solución completa de membresías compuesta por tres capas: La membresía debe registrar todas las empresas del país que deseen dar privilegios a una multitud de clientes que se deben afiliar al sistema por medio de la app o la web. 1. Backend seguro en Spring Boot • API REST documentada (OpenAPI) • Gestión de usuarios, control de acceso por roles, historial de pagos y registro detallado de cada proceso • Integración con pasarelas de pago (Stripe u otra equivalente) • Autenticación JWT y refresco de tokens • Base de datos relacional (PostgreSQL) con migraciones versionadas 2. Panel administrativo web en React + Vite • Dashboard para crear, editar y suspender me...

    $3632 Average bid
    $3632 Avg Bid
    93 bids

    Recommended Articles Just for You